Prove all things: hold fast that which is good.-- 1 Thess. 5:21.

In speaking from this text, I remark,

1. That it enjoins the duty of fundamental and thorough inquiry on religious subjects. It requires us to know the reason of our faith and practice, that our piety may not be superstition, but the result of intelligent conviction, arising from thorough investigation.

2. In order to fulfill this requirement, the mind must be free from prejudices on religious subjects. So long as prejudices exist in any mind, it is impossible that it should examine religious opinions with any such spirit as will admit of obedience to this precept. All its views will be perverted just in proportion as it is uncandid and prejudiced.

3. This precept assumes the fact of our ability to 'prove all things.' The ability to comply with any requirement is always implied in the requirement. Otherwise the command is unjust.

4. This precept implies the necessity of correct information on religious subjects. The sentiment that it is immaterial what our opinions are, seems to prevail extensively among men, but it is plainly a mistake. Men can never be expected to remain rooted and grounded in the truth any farther than their opinions are true. All observation and experience prove this, and such is the concurrent representation of the Bible.

5. This command is given to all; not merely to ministers, but to laymen and women. Each is required to examine for himself, and to call no man master, so as to receive his "ipse dixit" as authoritative. It requires each one to know for himself the reasons of his faith.

6. The great mass of mankind don't love to think closely. They would prefer to do almost any thing else. They are like school-boys who shun the labor of study, and go to be taught without having studied their lesson. What they are told they forget before the next recitation.

7. I shall address myself, in this lecture, to those, and those only, who will be at the trouble to think. To address others would but be a waste of time and strength. Those who will not think cannot be saved.

8. I will neither spend my time, nor endanger your souls, by random exhortation and appeal, but strive to follow the spirit of the text.

9. My object is not controversy; I hope wholly to avoid its spirit, and, as far as possible, even its form. On the contrary, it will be my object as far as possible, to present what I honestly believe to be the truth to the consideration of the honest and truth-loving.

10. There is but little obedience to the requirement in the text, and as a consequence great ignorance and error prevail on many questions of fundamental importance. There are very few who can give any rational account of what constitutes sin and holiness, moral obligation, or human responsibility.

11. The terms which represent the attributes of Christian character, or what are commonly called the Christian graces, are almost never rightly defined. The definitions which are given scarcely ever represent the right idea, for example, of love, faith, repentance, self-denial, and humility. It is manifest that but few know how to define them. Why? Because they have not complied with the requirement of the text. And because these attributes of holiness are not rightly defined, they are misunderstood, and the result is that they are not exhibited in the lives of Christians. We see one picture drawn in the Bible, and quite another in real life. The former is beautiful and glorious, the latter--how sadly deformed. Why? Because the mass are mistaken, and mistaken as the result of incorrect views respecting the nature of true piety.

12. The distinction between natural and revealed theology should be understood and appreciated. Indeed, it is fundamental to an understanding of the Bible, for the Bible both assumes the truths of natural theology, and that we understand them; for example, that we exist, the existence of God, our moral agency, natural ability, the distinction between right and wrong, &c. We do not, therefore, and can not rightly understand the Bible, unless we understand the fundamental truths of natural theology, which are taken for granted in the Bible.

13. Natural theology consists in those truths that we may learn from the book of nature. God has presented us with two books--that of nature, and that of revelation, and they are equally authentic, and mutually confirmatory of each other.

14. The Bible not only assumes, and in various ways confirms the truths of natural theology, but adds many truths not discoverable by unaided reason, but which are recognized as truths as soon as suggested.

15. Many err in supposing that because a truth is seen to be such in the light of its own evidence, when suggested, therefore it might have been discovered without inspiration. There are plainly multitudes of truths revealed in the Bible, which men could never otherwise have discovered, but which, now that they are discovered, are seen to be perfectly reasonable. It is one thing to apprehend and recognize truth, when made known, but quite another thing to discover it.

I bespeak your prayers and attention, while I proceed to show,

I. HOW WE KNOW ANY THING.

II. HOW WE KNOW EVERY THING WHICH WE DO KNOW.

III. SOME THINGS WHICH WE KNOW ABOUT OURSELVES, THE TRUTH, AND OUR KNOWLEDGE OF WHICH, ARE TAKEN FOR GRANTED BY INSPIRATION.

I. How we know any thing.

1. Consciousness is a condition of all knowledge. It is the mind's recognition of its own existence, choice, thoughts and feelings. It is a knowledge of ourselves in the phenomena of our minds. The mind does not first observe its phenomena, and thence infer its own existence, for to attempt to prove this would be to assume as doubtful that which is absolute certainty and which must be so regarded in order to attempt proof or inferences, but it absolutely affirms its own existence, and consciousness testifies to this affirmation, saying, "I exist, I think, I feel, I will." Consciousness give both the I and its phenomena, that is its choices, thoughts and feelings, together with their freedom or necessity. Without consciousness knowledge would be to us impossible, for there is no other way of obtaining knowledge. How and what could one know, without knowing that he knows? and what knowledge would that be, of which you have no knowledge?

II. How we know every thing which we do know.

1. As our existence, and all our mental acts and states are given us by consciousness, it is plain that we know by consciousness every thing which we do know. For example. Suppose I have a sensation: How do I know that I have it? By consciousness. So it is with all our emotions, desires, choices, judgments, affirmations, denials, hopes, fears, doubts, joys, and sorrows. They are all given us by consciousness. I am now speaking what every man knows to be true.

2. Nothing without us is known to us only as it makes an impression upon our minds which impression is revealed to us by consciousness.

3. What we know by consciousness we know with certainty, that is, we know that our existence, acts, thoughts, and feelings are realities.

4. Consciousness is therefore the highest possible evidence. We do, and cannot but rely upon it as conclusive. If I think, feel, or act, I know that I think, feel, or act, and know it absolutely. It is impossible from our very constitution to doubt its testimony.

5. But we should carefully distinguish between what is really revealed to us by our consciousness, and inferences drawn from such revelations. We may mistake the cause of a sensation, but not the sensation. When God spoke to Christ from Heaven, the people who heard were conscious of the sensation upon the auditory nerve. Here was no mistake. But they mistook its cause. They said, it thundered. So, in forming our various judgments and opinions we may mistake, but when consciousness testifies that we do judge or form an opinion, in this we cannot be mistaken.

III. Some things that we know about ourselves, the truth of which, and our knowledge of which are taken for granted by inspiration.

1. We know that we exist, and we know it so certainly that to ask for evidence is absurd. It is to assume that as doubtful which must be assumed as absolutely true in order to prove any thing true.

2. We know that we perform certain mental acts, and are the subjects of certain mental states. For example: we know that we originate choices and volitions, and are the subjects of thought and feeling.

3. Hence we know that we possess certain faculties and capacities, that is, we are capable of acts, thoughts, and feelings.

4. We know that these faculties, as also their products, are capable of being classified. All men naturally classify them. They never confound thinking with feeling, feeling with willing, nor willing with either of them. No child does this. Nor do they confound the power of thinking, or of feeling with that of willing, or with one another.

5. Hence all men, although they may not understand the terms employed by philosophers to represent the natural faculties, notwithstanding, fully understand the thing intended by these terms. They know themselves to possess those faculties which we call intelligence, sensibility, and free will. We think, feel, and will, and therefore we know that we have the faculties of thinking, feeling, and willing, and mental philosophy is nothing else than an analysis of what all men are conscious of. Under the general term intelligence we include consciousness, reason, and understanding. All thoughts, affirmations, intuitions[,] judgments, and inferences, are the product of the intelligence.

6. We are conscious of our own liberty in the sense of having ability to choose in any direction in view of motives--to choose or refuse any object of choice. We know this with absolute certainty. This is an intuition of reason revealed by consciousness, and however men may deny their own freedom, in theory, yet they always act upon the assumption that mankind are free.

7. We are conscious that we can voluntarily control some of our capabilities, and some we cannot; for example; the voluntary, and involuntary muscles. If I will to move my arm, it moves in obedience to my will, but if I will that my heart shall cease to beat it still continues to beat wholly regardless of my will. In like manner we know that some of our capabilities are directly under the control of the will, and some indirectly.

8. We know by consciousness that muscular action is directly necessitated by our will--that there is a necessary connection between volitions and outward action. Some have made freedom to consist in doing as we please, or as we will; but that there is no freedom in this, every one knows, for when I will to move my arm, or to perform any other outward action, the action takes place by a natural necessity. While the volition exists, the outward action must be.

9. We also know by consciousness that thought and feeling are only indirectly subject to the will. Suppose, for instance, you wish to transfer your thoughts from one object to another. You cannot do this directly, and yet you are conscious that you can indirectly through the attention. Hence by directing the attention to any given subject upon which you wish to think, thought is the necessary result. So if you abstract the attention from an object upon which you do not wish to think you thus indirectly abstract the thoughts from it. Even children know this with absolute certainty. So with feeling of every kind. We are conscious that we cannot directly feel by willing to feel. Suppose, for example, we wish to call into being the feelings of love, hope, fear, joy, or sorrow. We are conscious that we cannot, by direct willing, create these feelings, or even modify them. But, nevertheless, we are conscious that we can indirectly regulate the feelings to a great degree. For example: If we wish to experience the emotions produced by the beautiful, we turn our attention to a beautiful object, and the emotions arise of course. On the contrary, by turning our attention to an offensive object, we can indirectly produce disagreeable emotions in our own minds. The same law operates respecting all religious feelings. They can to a very great degree be regulated indirectly by the will through the attention, but never directly.

10. We know by consciousness that whatever we can do at all, we can do by willing and that whatever act or state is not connected with the action of our will is impossible to us by a natural necessity. Suppose, for example, I will to move, but suddenly the nerves of voluntary motion are paralyzed, so that they will not obey my will. Then to move is impossible for me. The same is true of thoughts and feelings. If I will to expel certain thoughts and feelings from my mind, and to produce others, I abstract my attention from those objects on which it rests and direct it to other objects. This course will universally change the existing thoughts and feelings, but if it should not, then to change them is impossible for me. So of every thing else. Whatever we cannot accomplish by willing, we cannot accomplish at all. This is universal experience.

11. We are conscious of possessing in our intelligence a faculty, called reason, or the intuitive faculty, by which we perceive and affirm absolutely certain truths which carry with them their own evidence. This faculty gives us, when certain conditions are fulfilled, all necessary, absolute and universal truths. It is so infallible, and uniform in its affirmations, that whenever the terms of a proposition are understood, every reason in the world will affirm the same things. For example, mathematical truths, as that two and two equal four, or things which are equal to the same thing are equal to one another. These affirmations are so absolute that the mind cannot doubt them.

12. Among these self-evident truths are al[l] the first principles of morals such as--(1.) Tha[t] there is such a thing as right and wrong, and that the difference between them is fundamental. (2.) That the existence of these implies moral law. (3.) That men have moral character. (4.) That moral character implies moral obligation. (5.) That moral obligation implies moral law and moral agency. (6.) That moral agency implies natural ability. (7.) That natural ability implies the existence of intelligence, sensibility and freewill, that is, that moral agents actually know, feel, and will. The mind does not call for proof of these things, but affirms them as absolute verities, and the Bible therefore assumes them as true. It assumes that moral agents do actually know, feel and will. (8.) That moral character does not and cannot belong to the constitution of either body or mind, since it is impossible that a moral being should be either praise or blameworthy for his constitution. But moral character is necessarily either praise or blameworthy. It cannot thus belong to the constitution. (9.) That the constitutional appetites, desires and passions can have no moral character in themselves, since they are in themselves involuntary. For example, the appetite for food. Suppose yourself hungry, and in the presence of food. The appetite will naturally demand it from the very constitution, and can therefore in itself have no moral character. The same is true of desires and passions whenever you are in the presence of objects adapted to awaken them. (10.) This intuitive faculty affirms, that on the will's consenting to gratify any of these appetites, desires or passions under forbidden circumstances, there is sin. For example, when Eve saw the fruit, her appetite naturally craved it. In this there was nothing wrong, but when she consented to gratify her appetite, not withstanding it was prohibited, this was supreme selfishness. Had it not been prohibited the gratification would have been proper, but being prohibited, it was sin. It is the same respecting the gratifying of any desire or passion whatever. (11.) This intuitive faculty asserts that moral character cannot belong to any involuntary act or state of mind whatever, nor to any outward actions. If I stab a man, the moral character of the act does not belong to the dagger, nor to the hand which held it, nor to the muscles of the arm, nor to the volition which impelled the arm, but to the intention. (12.) It also asserts that moral character cannot belong to the states of the sensibility, that is, to the various emotions or feelings, for these are necessary; nor to the states of the intelligence. There is no virtue in the perception of truth. Devils, and wicked, as well as good men, perceive truth, and doubtless think correctly on many subjects, and their reason affirms moral truths, but there is no virtue in this. (13.) It also asserts that moral character cannot belong to volitions as distinguished from choices, for choice or intuition necessitates volition for the time being. (14.) But it does assert that moral character belongs to the ultimate intention of the mind. Intention is the choice of an end. The ultimate intention is the last end chosen--that for which every thing else is chosen or done. I will illustrate the difference between ultimate and proximate intention. Suppose a young man laboring, and you inquire what he is laboring for. He says, to get money. This is one end. But ask again, what do you want of money? He says, to buy books. This is another end. Ask again, what do you want of books? He says, to get knowledge. This is another end. But continue the inquiry, what do you want of knowledge? He says, to preach the gospel. This is still another end. But you may ask farther, what do you want to preach the gospel for? He replies, to do good--because the good of the universe is valuable in itself. This is the last end--the ultimate intention, and all the previous ends are only means to this or what are called proximate ends. But in this case the whole moral character of all the process belongs plainly to the ultimate intention. In this all ethical philosophers, worthy of note at the present day, agree. It is plainly the doctrine of the Bible, and thus the Bible and natural theology are at one precisely. The truth is even children understand that character consists in ultimate intention. Pa, says the child in self justification, I didn't mean to do it. And the question between the child and his parent is about the intention. So it is in courts of justice. They always inquire for the "quo animo" or intention. In short, all men, whatever may be their theory, understand and act upon the truth of this doctrine. If a physician give medicine with a design to cure, he would be universally acquitted of blame, even though instead of curing the disease, it should take the life of a patient. In fact, this doctrine is so certain that the Bible could not be believed if it disagreed with it.