“So I always take pains to have a clear conscience toward both God and man.” (Acts 24:16)
God reveals his will in many ways: through conscience, instruction, commandments, principles, and living demonstration. Truth and goodness are defined by, and flow from, the nature of God. There is not some ultimate “way things are” that would seem to sit in judgment on God. There is no “nature of things” to which God must conform if he is to be good. No, he defines truth and goodness by being good and truthful. It is true that God reveals his existence and his power through creation (Rom. 1:18-20), but the only sure guide for truth and goodness is the supernatural revelation of the written Word of God through prophets and apostles.
The Roman Catholic church, following the theology of Thomas Aquinas (1224–1274), has relied more on “natural law” than have Protestants. Both recognize, however, that some knowledge of right and wrong, however dim and distorted, apart from the Bible, is stamped somehow in the consciousness of human beings. This Paul teaches clearly (Rom. 2:14-15).
Although the Old Testament does not use the term conscience, the idea is there, and it is explicitly taught in the New Testament. Conscience is no more and no less than one’s judgment in the moral realm. Naturally, this judgment is strongly conditioned, like all our judgments, by what we have learned from parents and society. Nevertheless, the Bible teaches that moral awareness is innate — everyone knows that there is right and wrong, though not all agree on precisely what. Our moral judgment is distorted by our cultural environment and therefore is not an adequate moral light to follow.
Not only does environment condition our judgment, man’s moral judgment is fallible, dimmed by his severe limitations of knowledge and wisdom. He doesn’t have all the data needed to make the right judgment, and he doesn’t have sufficient wisdom to evaluate the data he does have. Furthermore, his moral judgment is obscured by his separation from God, the source of moral light. His mind is inclined by sin to suppress the knowledge of the right, to distort the moral light he does have.
The human mind is like a computer of inadequate capacity, programmed with misinformation and short-circuited. Consequently, “Let your conscience be your guide” can be a dangerous maxim. Having said this, however, there is “the true light that enlightens every man . . . coming into the world” (John 1:9). And what a hell this world would be if God had not imprinted in man that moral likeness, however limited and blurred by sin.
A person’s moral judgment is untrustworthy, but it can be renewed and become increasingly reliable. This mind renewal about which the apostles speak so insistently is intimately bound up in the idea of conscience or moral judgment. The regenerated mind, molded by study of the Word of God, obedient and sensitive to the Holy Spirit, and constantly asking for enlightenment, will become increasingly reliable.
The thought process of the Christian is the means by which God transforms him into the likeness of his Son. Often in the writings of Paul, when we might have used heart he used mind, and when we might have used affections he used knowledge. Of course, this is knowledge in the Hebrew sense, so it is not merely intellectual apprehension of truth, but personal experience and commitment. Nevertheless, it is the mind that God is after, the mind that bears the imprint of his likeness, the mind that must be renewed so that its moral judgments are increasingly reliable. Even that great experience of the heart and ultimate achievement of the moral good, love, has to do with the mind. Christ, in quoting the Old Testament law of love for God, deliberately added what was not said by Moses (Deut. 6:5), that we should love him with all the mind (Matt. 22:37). God’s great mind-renewal program reprograms our moral judgment so that it becomes increasingly reliable.
Nevertheless, apart from the written, revealed will of God, even the renewed and Spirit-sensitized conscience is not wholly reliable. Revelation is essential.
In Scripture God reveals his will through instruction in right thinking and right behavior, through direct commandments, through principles, and through the example of good and bad behavior. Instruction seemed to be the primary mode before the time of Moses and in the New Testament, whereas commandments seemed the prominent mode during the era of “the law.” Examples of right and wrong conduct abound in the Old Testament, but the supreme model is found in Jesus Christ. Principles, for living, whether stated as such or derived from example and instruction, permeate the whole of Scripture.
How can you build confidence in knowing God’s will? What are you desiring to understand as God’s will? How can you use these principles to discern how to live and choose?
 1 Sam. 24:5; 2 Sam. 24:10; Jer. 31:33
 Acts 24:16; Rom. 2:14-15; 2 Cor. 1:12; 1 Tim. 1:5; 2 Tim. 1:3; Heb. 10:2, 22