by Wayne Blank
"But I say unto you, Swear not at all; neither by heaven; for it is God's throne: Nor by the earth; for it is His footstool: neither by Jerusalem; for it is the city of the great King. Neither shalt thou swear by thy head, because thou canst not make one hair white or black. But let your communication be, Yea, yea; Nay, nay: for whatsoever is more than these cometh of evil." (Matthew 5:34-37 KJV)
"he shall do according to all that proceedeth out of his mouth"
The principle of how, in the Scriptures, oaths were a solemn promise to do something, not an "oath" in the modern-day sense, can be illustrated by this example whereby The Lord made an oath to do something; obviously, The Lord, Who cannot lie, did not need to make an oath to tell the truth. In the Bible, "oath" is almost always used to describe a solemn pledge to do what one says will be done. Here The Lord made an oath "to perform the mercy promised to our fathers." This example also shows how prophecy is as much a matter of having the power to make something happen in the future, as it is being able to see it beforehand. Prophecy is often a matter of the materialization of stated long-range planning.
"As He spake by the mouth of His holy prophets, which have been since the world began: That we should be saved from our enemies, and from the hand of all that hate us; To perform the mercy promised to our fathers, and to remember his holy covenant; The oath which he sware to our father Abraham" (Luke 1:70-73 KJV)
Here are other examples of "oath" meaning a promise to carry out what one says one is going to do. Telling the truth is an integral part of that, but in the Bible it was moreover used as an obligation of action.
"Now therefore swear unto me here by God that thou wilt not deal falsely with me, nor with my son, nor with my son's son: but according to the kindness that I have done unto thee, thou shalt do unto me, and to the land wherein thou hast sojourned. And Abraham said, I will swear" (Genesis 21:23-24 KJV) (see also On His Own Two Feet)
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