Contradiction with Ecclesiastes 5:4
Warns against delaying to pay vows, implying one might not need to make a vow, while Psalms 116:14 encourages fulfilling vows made to the Lord.
Ecclesiastes 5:4: 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.
Contradiction with Matthew 5:34-36
Advises not to swear at all, contrasting with the notion of fulfilling vows in Psalms 116:14.
Matthew 5:34-36: But I say unto you, Swear not at all; neither by heaven; for it is God's throne:
Contradiction with James 5:12
Urges not to swear by any oath, contradicting the idea of making and fulfilling vows to the Lord in Psalms 116:14.
James 5:12: But above all things, my brethren, swear not, neither by heaven, neither by the earth, neither by any other oath: but let your yea be yea; and [your] nay, nay; lest ye fall into condemnation.