Don't Make Hasty Promises
And Jephthah vowed a vow unto the Lord, and said, If thou shalt without fail deliver the children of Ammon into mine hands, Then it shall be, that whatsoever cometh forth of the doors of my house to meet me, when I return in peace from the children of Ammon, shall surely be the Lord's, and I will offer it up for a burnt offering. So Jephthah passed over unto the children of Ammon to fight against them; and the Lord delivered them into his hands. And he smote them from Aroer, even till thou come to Minnith, even twenty cities, and unto the plain of the vineyards, with a very great slaughter. Thus the children of Ammon were subdued before the children of Israel. And Jephthah came to Mizpeh unto his house, and, behold, his daughter came out to meet him with timbrels and with dances: and she was his only child; beside her he had neither son nor daughter. And it came to pass, when he saw her, that he rent his clothes, and said, Alas, my daughter! thou hast brought me very low, and thou art one of them that trouble me: for I have opened my mouth unto the Lord, and I cannot go back. And she said unto him, My father, if thou hast opened thy mouth unto the Lord, do to me according to that which hath proceeded out of thy mouth; forasmuch as the Lord hath taken vengeance for thee of thine enemies, even of the children of Ammon. And she said unto her father, Let this thing be done for me: let me alone two months, that I may go up and down upon the mountains, and bewail my virginity, I and my fellows. And he said, Go. And he sent her away for two months: and she went with her companions, and bewailed her virginity upon the mountains. And it came to pass at the end of two months, that she returned unto her father, who did with her according to his vow which he had vowed: and she knew no man. And it was a custom in Israel, That the daughters of Israel went yearly to lament the daughter of Jephthah the Gileadite four days in a year. Judges 11:30-40 (KJV)
A vow is a promise. It can be made to God, other people, or oneself, although Scripture usually refers to vows to God. In this passage we see that Jephthah made a vow to God. He vowed that he would offer to God whatever came out of his house to greet him in exchange for the Lord giving him victory over the Ammonites. After his victory, the first to come out to greet him was a person- his only child, a daughter.
God forbade human sacrifice. Jephthah told his daughter about his vow to God, and she told him to keep his vow. Instead of human sacrifice, he offered her to the service of the Lord, as some parents did. (Consider Hannah, who offered her son Samuel to the Lord.) For two months, his daughter was permitted to mourn her virginity upon the mountains. After that time, she was dedicated to the Lord, and she never knew a man, meaning she never married. This was a costly vow, but Jephthah (and his daughter) kept it.
If we make a vow, a promise, we are to keep it. The Bible says it is better not to make a vow than to make one and break it (Ecclesiastes 5:5). If you make a promise, always count the cost, determining in your heart whether you can really keep it. Consider whether it is in the best interest of everyone involved. If not, don’t make the promise or vow.
Those who despise flagrant sinners, and honor the faithful followers of the Lord, and keep their promises even when it hurts.Psalm 15:4 (New Living Translation, NLT)
When we make a promise, we are to keep it, even if it costs us to do so. If circumstances change or for some reason beyond our control we cannot fulfill our vow, we must go the person to whom we made the promise to explain and apologize, making restitution if necessary. And learn from your mistake to avoid repeating it.
Jesus told us to let our yes be yes and our no be no- any more than this comes from the evil one. Don’t let the enemy use your words against you to defeat you. It is okay to make promises- as long as we can keep them and it is for the good of all involved. Think before you promise anything to anyone. Don’t make hasty promises.
When thou vowest a vow unto God, defer not to pay it; for he hath no pleasure in fools: pay that which thou hast vowed. Better is it that thou shouldest not vow, than that thou shouldest vow and not pay. Suffer not thy mouth to cause thy flesh to sin; neither say thou before the angel, that it was an error: wherefore should God be angry at thy voice, and destroy the work of thine hands? Ecclesiastes 5:4-6 (KJV)