'O God' in the Bible

and they were helped against them, and the Hagarites were delivered into their hand, and all that were with them; for they cried to God in the battle, and he was intreated of them, because they put their trust in him.

And say, Save us, O God of our salvation, And gather us, and deliver us from the nations, To give thanks unto thy holy name, To triumph in thy praise.

And this hath been a small thing in thy sight, O God; and thou hast spoken of thy servant's house for a great while to come, and hast regarded me according to the rank of a man of high degree, Jehovah Elohim.

And David said to God, I have sinned greatly, in that I have done this thing; and now, I beseech thee, put away the iniquity of thy servant; for I have done very foolishly.

And David said to God, Is it not I that commanded the people to be numbered? It is I that have sinned and done evil; but these sheep, what have they done? Let thy hand, I pray thee, Jehovah my God, be on me and on my father's house; but not on thy people, that they should be smitten.

and his brethren, men of valour, two thousand seven hundred chief fathers, whom king David made rulers over the Reubenites and the Gadites and the half tribe of the Manassites, for every matter pertaining to God, and the affairs of the king.