Matthew 5:36

Neither shalt thou swear by thy head, because thou canst not make one hair white or black.

No one is to swear by his own head to back up his word, for he has no power to make even one hair white or black. Nothing can rightfully be pledged as one's own, for a person owns nothing and controls nothing, since all things come from God and all have been bought by the blood of Christ. Common oaths and exaggerated speech in everyday talk, including swearing by one's life or head, calling heaven or earth to witness, or invoking ruin on oneself if untrue, are therefore no sound guarantee and are forbidden. A solemn oath before God and a judicial oath when lawfully called to testify to the truth are not forbidden. The prohibition reaches to the spirit of the law in the heart, where life and character are regulated, for human opinion cannot give character, and each stands answerable before God for what he himself is.

Setting in the Sermon

Matthew 5:36 belongs to Christ's blessings and instructions on the mount, whose symbols carry deep meaning and are meant to be incorporated into practical life. It belongs to Christ's exposition of the far-reaching principles and claims of the law, restoring them from human traditions to their proper meaning. The law so expounded is holy, just and good and remains the standard of righteousness, reaching to the spirit of the law in the heart. The state of the heart regulates life and character, so instruction of new converts must impress these broad principles upon the heart, or labor for them is lost.

The verse is part of Christ's teaching of the principles and conditions of entrance into God's kingdom and the principles governing the kingdom of divine grace. He did not in this teaching promise worldly greatness, earthly glory, or national restoration. His teaching contradicted the teachings and practices of the self-righteous scribes and Pharisees and challenged their misrepresentation of God.

Christ thereby set aside the continually repeated They say and It has been said of the rabbinical schools of His day as corrupting to the mind. Those sayings are unstable words of men and are not to be accepted as exalted wisdom. No one should be encouraged to attend schools where they are taught when a greater and certain wisdom from God is at command. The verse is part of the pure gospel given upon the mount that explains God's holy law.

That gospel sets the holy standard of character for business transactions, requiring love to God with the whole heart and love to neighbor as God requires. It forbids mingling human wisdom with the divine, confusing minds about right and holy methods, and unjustly acquiring means at another's expense. Those who do these things prove they have not yet learned the law and its explanation. They need a cleansing and purging of the soul temple.

Meaning of the Prohibition

Neither is the head to be sworn by, for no person has power over it to decide whether even one hair shall turn white or black. The inability to control so small a thing is given as the reason for the prohibition. Nothing is owned in a way that could be pledged, for all things come from God and there is nothing that has not been received. More than this, there is nothing that has not been purchased by the blood of Christ, with everything possessed stamped with the cross and bought with blood precious above all estimate because it is the life of God, so nothing can rightfully be offered as one's own to guarantee the fulfillment of one's word.

The warning reaches to oaths in ordinary conversation and to exaggerated speech used to back a claim, since the head is no sound guarantee. This includes swearing by one's life or head to assure others that a statement is true, calling heaven or earth to witness, or invoking one's own destruction if the statement is false. A solemn oath before God is not forbidden, nor is a judicial oath when a person is lawfully called to testify and it is necessary to affirm that what is said is true.

Heart Character and Conduct

The prohibition belongs to the sermon on the mount that sets forth the far-reaching principles of God's law. Those claims reach to the spirit of the law in the heart. This is because the state of the heart regulates life and character. Instruction of new converts must impress these broad principles upon the heart, or labor for them is lost.

The prohibition belongs to instruction that disciples must learn and obey in order to develop Christlike character. That Christlike character is contrary to accusing and faultfinding. It supports love, unity, and Christian fellowship among followers. The inability to make one hair white or black shows that human opinions and judgments cannot give character whiteness or blackness. Character is what a person makes it in the sight of a pure, holy and just God, and each stands before God answerable for what he himself is in His presence, not answerable for the course of others.