Neither shall you swear by your head, because you cannot make one hair white or black.
We see the Lord’s new law regarding swearing: it is not to swear at all. The new law of the kingdom forbids the kingdom people to swear in any manner, by the heaven, by the earth, by Jerusalem, or by their head, because the heaven, the earth, Jerusalem, and their head are not under their control, but under God’s. We should not swear by either the heaven or the earth, for they are not ours. Likewise, we should not swear by Jerusalem because, as the city of the great King, it is not our territory. We should not even swear by our head because we “cannot make one hair white or black.” All these things—heaven, earth, Jerusalem, and even the hairs of our head—are not under our control. We are nobody and we control nothing.