'O God' in the Bible

But, the messenger of Yahweh, spake unto Elijah the Tishbite, Rise, go up to meet the messengers of the king of Samaria, - and say unto them - Is it, because there is no God in Israel, that, ye, are going to enquire of Baalzebub, god of Ekron?

And they said unto him - A man, came up to meet us, and said unto us - Go, return unto the king who sent you, and ye shall say unto him, Thus, saith Yahweh - Is it, because there is no God in Israel, that, thou, art sending to enquire of Baalzebub, god of Ekron? Therefore, from the bed whereunto thou hast gone up, shalt thou not come down, for thou shalt, surely die.

and said unto him - Thus, saith Yahweh - For that thou didst send messengers to enquire of Baalzebub, god of Ekron, was it because there was no God in Israel, for whose word thou couldst enquire? Therefore, from the bed whereunto thou hast gone up, shalt thou not come down, for thou shalt, surely die.

And he returned unto the man of God, he and all his company; and came, and took his stand before him, and said - Lo! I pray thee - I know that there is no God in all the earth, save in Israel, - now, therefore, I pray thee, accept a blessing from thy servant.