What does it mean to “swear to your own hurt”?
“Lord, who may abide in Your tabernacle? Who may dwell in Your holy hill?”
“… He who swears to his own hurt and does not change.”
Psalm 15:1, 4 NKJV
“In every business transaction be rigidly honest. However tempted, never deceive or prevaricate in the least matter. At times a natural impulse may bring temptation to diverge from the straightforward path of honesty, but do not vary one hairsbreadth. If in any matter you make a statement as to what you will do, and afterward find that you have favored others to your own loss, do not vary a hairsbreadth from principle. Carry out your agreement. By seeking to change your plans you would show that you could not be depended on. And should you draw back in little transactions, you would draw back in larger ones. Under such circumstances some are tempted to deceive, saying, I was not understood. My words have been taken to mean more than I intended. The fact is, they meant just what they said, but lost the good impulse, and then wanted to draw back from their agreement, lest it prove a loss to them. The Lord requires us to do justice, to love mercy, and truth, and righteousness.” Child Guidance, 154.
“The obligation to which one’s word is pledged—if it does not bind him to perform a wrong act—should be held sacred. No consideration of gain, of revenge, or of self-interest can in any way affect the inviolability of an oath or pledge. ‘Lying lips are abomination to the Lord’ (Proverbs 12:22). He that ‘shall ascend into the hill of the Lord,’ and ‘stand in His holy place,’ is ‘he that sweareth to his own hurt, and changeth not’ (Psalms 24:3; 15:4).” Patriarchs and Prophets, 506.
“Better not to vow than to vow and not pay” (Ecclesiastes 5:5 NKJV).