Promises, Promises … (Matt. 5:33-37)
The first two antitheses(murder and adultery) are based on the Decalogue. The antithesis regarding divorce and the ones that follow are taken from other sections of the Mosaic law, including the one about swearing falsely and performing oaths to the Lord.
The Mosaic law, from which Jesus quotes, is listed in a section of Leviticus that condemns a number of deceptive practices. Here again it is evident that Jesus’ concern is with the intentions. Anyone who makes a promise with no intention of fulfilling it has made a conscious decision to sin.
Though the command against swearing falsely relates to promises made to other people, the second command concerns promises made to God.
Unlike the person guilty of false swearing, the one who makes a financial pledge to God is not necessarily intending to defraud. However, Jesus knows human nature and cautions against making promises that one may later regret. Rather than making promises that may not even be in the power of the individual to fulfill, a Christian should be a person of integrity whose yes means yes and nomeans no.