“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. ~ Matthew 5:33-37.
Our language and conduct must be such that we need not invoke oaths to make people believe we are telling the truth.
“oaths” (v.33) — This was an allusion to several OT texts. This did not mean cursing, but God’s name being brought into a conversation to assure the truth of one’s statements (cf. Matt. 23:16-22; James 5:12). Vows or oaths in the OT could refer to (1) worship (cf. Deut. 6:15); (2) legal proceedings (cf. Exod. 20:7; Lev. 19:12); or (3) affirmations of doing something (cf. Leviticus 27; Num. 30:2; Deut. 23:21-22). Jesus was involved in an oath in Matt. 26:63-64. Paul made oaths in 2 Cor. 1:23, Gal. 1:20, Phil. 1:8, and 1 Thess. 2:5. Another oath is found in Heb. 6:16. The focus is not on oath taking, but on failing to perform the vow!
“But I say to you … white or black” (v.34-36) — This showed how elaborately the rabbis had developed binding and unbinding oaths (cf. Matt. 23:16-22). It was a way to appear to be telling the truth by associating one’s statement with Deity, but all the time knowing that one’s oath, expressed in certain ways, was not legally binding.
“do not swear at all” (v.34) — Jesus testified under oath in Matt. 26:63-64. Paul often confirmed his words by oaths in God’s name (cf. 2 Cor. 1:23; Gal. 1:20; Phil. 1:8; 1 Thess. 2:5,10). The issue is truthfulness, not restricting oaths (cf. James 5:12).
“But let your ‘Yes’ be ‘Yes,’ and your ‘No,’ ‘No’” (v.37) — Jesus was concerned with truthfulness, not form! Others who claim to know God should be honest and trustworthy, not tricky.