'O God' in the Bible

Then Moses cried to the Lord, "Heal her now, O God."

Then they threw themselves down with their faces to the ground and said, "O God, the God of the spirits of all people, will you be angry with the whole community when only one man sins?"

Balaam said to God, "Balak son of Zippor, king of Moab, has sent a message to me, saying,