Matthew 5:33-37New King James Version (NKJV)
33 “Again you have heard that it was said to those of old, ‘You shall not swear falsely, but shall perform your oaths to the Lord.’ 34 But I say to you, do not swear at all: neither by heaven, for it is God’s throne; 35 nor by the earth, for it is His footstool; nor by Jerusalem, for it is the city of the great King. 36 Nor shall you swear by your head, because you cannot make one hair white or black. 37 But let your ‘Yes’ be ‘Yes,’ and your ‘No,’ ‘No.’ For whatever is more than these is from the evil one.
The Law was put in place because God knows that in our everyday life we are careless with our words and casually lie or evade the truth. We make promise we have not intention to keep and use our promises and our words to get people off of our backs. There is a casual nastiness about the way we use the God given gift of speech and the jot and tittle here is that one is doomed by being forced to keeping one’s every word (Matt. 5:33-37).
“The Law therefore requires the oath, in order to invade the normal secularity of man’s speaking, in order that man may be brought to speak responsibly before God, for this once at least, by way of exception if nothing more. Jesus removes not only the casuistry of oaths but the oath itself (Matt 5:34- 36). The disciple, in the new situation created by the Christ, says Yes and says No, and that is oath enough; for his every word is spoken in responsibility to God, is spoken in the presence of the God who has drawn near to him in His Son; his every word is an oath. The disciple knows that everything beyond that simple Yes and No comes from the Evil One (Matt 5:37), who casts the gray veil of secularity over man’s words and conceals from men the fact that words have on them the accent of accountability, so that men come to think they can “say things,” and ignore the fact that there is a God who will judge every idle word of man (Matt 12:36,37). The repentant disciple has spoken a whole assent to God and with that assent has renounced the devil and all his works and all his delusions. “Against such there is no law” (Gal. 5:23), for in them the will of the Law (that men speak before God) is affirmed, while that which made the Law impotent has been removed.” From Follow Me: Discipleship According to St. Matthew (c) 1961 CPH. Used with permission.