Acts 23:12
And when it was day, some of the Jews banded together and bound themselves under an oath, saying that they would neither eat nor drink till they had killed Paul.

Everyone makes oaths, vows, and promises they cannot keep. Perhaps they have good intentions but other things get in the way.
Many people make a promise believing they will not have to fulfill it.
These Jews made an oath they cannot keep. Their oath made against Paul is really against God.
These men forgot the word of God which says in Eccl 5:4-5: When you make a vow to God, do not delay to pay it; For He has no pleasure in fools. Pay what you have vowed —
Better not to vow than to vow and not pay.
You need to also remember to pay your vows. It’s a debt you do not want to carry with you.
I can only assume those Jews starved to death or died of thirst since they never killed Paul.