Why in court. do we swear an oath on the Bible, when the Bible expressly forbids taking oaths?
There are about 30 biblical references to vows, most of which are from the Old Testament. The books of Leviticus and Numbers have several references to vows in relation to offerings and sacrifices. There were dire consequences for the Israelites who made and broke vows, especially vows to God. The story of Jephthah illustrates the foolishness of making vows without understanding the consequences. Before leading the Israelites into battle against the Ammonites, Jephthah—described as a mighty man of valor—made a rash vow that he would give to the Lord whoever first came out of doors to meet him if he returned home as the victor. When the Lord granted him victory, the one who came out to meet him was his daughter. Jephthah remembered his vow and offered her to the Lord (Judges 11:29-40). Whether Jephthah should have kept this vow is dealt with in another article. What this account shows us is the foolishness of rash vows. Perhaps this is why Jesus gave a new commandment concerning vows. “