'O God' in the Bible

And they were helped against them, and the Hagrites and all who [were] with them were given into their hand, for they cried out to God in the battle, and he responded to their prayer because they trusted in him.

Then say, "Save us, O God of our salvation; gather us and rescue us from the nations that [we may] give thanks to your holy name [and] glory in your praise.

And this was a small [matter] in your eyes, O God. And you have spoken concerning the house of your servant for a long [time] and have shown me {future generations to come}, O Yahweh God.

O Yahweh, there is none like you, and there is no God except you, according to all that we have heard with our ears.

Then David said to God, "I have sinned severely [in] that I have done this thing. But now, please forgive the sin of your servant, for I have been very foolish."

Then David said to God, "Was it not I [who] gave a command to count the people? Now I [am] he who has sinned, and I have certainly done wickedness, but these sheep, what have they done? O Yahweh, my God, please let your hand be against me and against the house of my father, but against your people, [let there be] no plague."