Show us which one of these two you have chosen to assume the task of this service and apostleship from which Judas turned aside to go to his own place.” Then they cast lots for them, and the one chosen was Matthias; so he was counted with the eleven apostles. – Acts 1:24-26
Some people believe that the apostles totally missed it here. Do you think that using the casting of lots to determine the next apostle seems crazy? I’ve heard it suggested that God chose Paul to be the twelfth apostle.
Casting lots may not be the best or most prescribed way of hearing from God, but it does have a Biblical precedent. In Leviticus 16:8, the priests were to cast lots to determine which of two goats would be the scapegoat. In Joshua 18, God told Joshua to cast lots to determine which group got to take which section of the land of Israel. In 1 Chronicles 24:31, Saul cast lots to find out who had broken the foolish commandment he had given. The sailors cast lots to find out that it was Jonah who had offended God.
God never warns against the casting of lots as an unreliable way of determining His will, that I have found. It may not be the best way. Listening to God and hearing His voice trumps casting lots any day—but we have to admit that God can even determine the flip of a coin.