'O God' in the Bible

But the angel of the LORD said to Elijah the Tishbite, "Arise, go up to meet the messengers of the king of Samaria, and tell them, 'Is it because there is no God in Israel, that you go to inquire of Baal Zebub, the god of Ekron?

They said to him, "A man came up to meet us, and said to us, 'Go, return to the king who sent you, and tell him, "Thus says the LORD, 'Is it because there is no God in Israel, that you send to inquire of Baal Zebub, the god of Ekron? Therefore you shall not come down from the bed where you have gone up, but shall surely die.'"'"

He said to him, "Thus says the LORD, 'Because you have sent messengers to inquire of Baal Zebub, the god of Ekron, is it because there is no God in Israel to inquire of his word? Therefore you shall not come down from the bed where you have gone up, but shall surely die.'"

He returned to the man of God, he and all his company, and came, and stood before him; and he said, "See now, I know that there is no God in all the earth, but in Israel. Now therefore, please take a gift from your servant."

and have cast their gods into the fire; for they were no gods, but the work of men's hands, wood and stone. Therefore they have destroyed them.