Law of Noncontradiction

God is not man, that he should lie, or a son of man, that he should change his mind. Has he said, and will he not do it? Or has he spoken, and will he not fulfill it?” (Num. 23:19).

- Numbers 23:19

Unfortunately, many modern Christians do not consider the mind to be all that important in the Christian life. This is largely due to the fact that many academics in the church have betrayed orthodoxy and have used their minds to mount an assault on Christian belief. In seeking to preserve the truth, many evangelicals have sought to accept Christian doctrine solely on faith. This is not necessarily unacceptable, except that they have defined faith as being incompatible with reason.

Faith and reason, however, belong together. Apart from faith, reason leads to futility. Without reason, faith becomes a blind leap that embraces contradictions. We see how this happens when people accept contradictory interpretations of Scripture as being equally true.

But God cannot contradict Himself. If He did, we could not believe what He says or know how to follow Him. If two people give a contradictory understanding of a text, either one of them is wrong or both of them are wrong. Both, however, cannot be right. Otherwise, the concept of truth loses all meaning.

God’s judgment on disobedience proves the point. God punished Adam and Eve for eating what He told them not to eat. If contradiction and truth were compatible, God could not have condemned Adam. How could God find them guilty if His prohibition against eating the fruit really could mean “do not eat the fruit” and “you may eat the fruit” at the same time and in the same sense?

God’s judgment on disobedience demonstrates that the Bible assumes the existence of one of the fundamental laws of reason, the law of noncontradiction. This law states that “A cannot be both A and non-A at the same time and in the same relationship.” In this proposition, “A” refers to an object being discussed. For example, “A” could be grasshoppers. “Non-A” refers to any other object that is not “A.” For the purpose of our example, “non-A” could be whales, tables, cars, bluebirds; anything except grasshoppers. Thus we arrive at the proposition: Grasshoppers cannot be both grasshoppers and whales (not grasshoppers) at the same time and in the same relationship.

The law of noncontradiction is vital to the intelligibility of faith and life. Without it, the concept of truth loses all meaning. Tomorrow we will explore the law further and see its use in life and theology.

Coram Deo

The Lord of the Universe is trustworthy. When He reveals Himself to us, He reveals Himself truly. If contradiction and truth could exist side by side, we would be left with a God whom we could never know or trust. Thank the Lord for His truthfulness and remember that when God tells us about Himself, He tells the truth.

Passages for Further Study

Prov. 14:5
Isa. 45:18–19
John 16:13
Heb. 6:17–18­

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