Is a vow to offer candles or oil to places containing graves valid?

Primary text

A vow to offer candles (sham') or oil (zayt) and similar items to places containing graves is invalid. This prohibition stems from the general principle forbidding the glorification of things not sanctioned by God, which resembles the idol worship condemned by the Prophet, peace be upon him, who cursed those who made graves into mosques and those who lit lamps upon them, warning against imitating the Jews who made the graves of their Prophets into mosques.