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.
Matthew 5:33-37
All things come from God. We have nothing that we have not received; and, more than this, we have nothing that has not been purchased for us by the blood of Christ. Everything we possess comes to us stamped with the cross, bought with the blood that is precious above all estimate, because it is the life of God. Therefore there is nothing that we have a right to pledge, as if it were our own, for the fulfillment of our word.
The third commandment was spoken by God and then written by the finger of God into stone (see Exodus 20:7′ Exodus 24:12) was understood by the Jews as prohibiting the profane use of the name of God. Yet they thought themselves at liberty to employ other oaths. Oath taking had become common among them. Yet Moses had forbidden them to swear falsely. Over time they have devised many devises for freeing themselves from the obligation imposed by oath. They did not fear to indulge in what was really profanity, nor did they shrink from perjury so long as it was veiled by some technical evasion of the law.
Jesus declared that their custom in oath taking was a transgression of the Commandment of God, Yet our Saviour did not forbid the use of judicial oath in which God is solemnly called to witness that what is said in truth and nothing but the truth.
At His own trail before the Sanhedrin Jesus did not refuse to testify under oath. When the high priest said to Him, “I adjure You by the living God, that You tell us whether You be the Christ, the Son of God.” Jesus answered, “You have said,” Matthew 26:63, 64.
So many of us do not fear to deceive our friends, business associates or anyone around, yet they have been and impressed by the Spirit of God, that it is a terrible thing to lie to their Maker and Redeemer. When placed under judicial oath they are made to feel that they are not testifying merely before men, but also before God. If they bear false witness, it is to Him who reads the heart and who knows the exact truth that stands in judgment.
But if there is anyone who can consistently testify under oath, it should be the Christian for he lives constantly in the presence of God, knowing that every thought is open to the eyes of Jesus.
But Christ took this one step further in laying down a principle that would make oath taking needless. He teaches that the exact truth should be the law of all speed. “Let your speech be Yes, a yes; and your no, a no and whatsoever is more than these is of the evil one.
These words condemn all the meaningless phrases and expletives that border on profanity. They bring into question the deceptive compliments, the evasion of truth and the flattering phrases, the exaggerations and the misrepresentation that we often call a white lie and that includes those who represent themselves as something they are not. They also apply to those that speak, yet their words do not convey the true sentiment of their heart.
Everything that Christians do should be as transparent as the sunlight. Truth is of God; deception, in every one of its myriad forms, is of Satan; and whoever in any way departs from the straight line of truth is betraying himself into the power of the wicked one. Yet it is not a light or an easy thing to speak the exact truth. We cannot speak the truth unless we know the truth; and how often preconceived opinions, mental bias, imperfect knowledge, errors of judgment, prevent a right understanding of matters with which we have to do! We cannot speak the truth unless our minds are continually guided by Him who is truth
Through the apostle Paul, Christ bids us, “Let your speech be always spoken with grace.” “Let no corrupt communication proceed out of your mouth, but that which is good to the use of edifying, that it may minister grace unto the hearers.” Colossians 4:6; Ephesians 4:29.
In the light of these scriptures the words of Christ upon the mount are seen to condemn jesting, trifling, and unchaste conversation. They require that our words should be not only truthful, but pure.
Those who have learned of Christ will “have no fellowship with the unfruitful works of darkness.” Ephesians 5:11. In speech, as in life, they will be simple, straightforward, and true; for they are preparing for the fellowship of those holy ones in whose mouth “was found no guile.” Revelation 14:5.
The Bible In Your Hand 