'O God' in the Bible

So God gave Daniel favour and grace before the chief chamberlain,

I thank thee, and I praise thee, O God of my fathers, Who hast given me wisdom and might, And hast made known unto me already what we desired of thee; For thou hast made known unto us the king's matter.

Therefore I will and command, that all people, kindreds and tongues, which speak any blasphemy against the God of Shadrach, Meshach, and Abednego, shall die and their houses shall be prised: Because, there is no God that may save, as this."

But you have been lifting yourself up against the Lord of heaven, and they have put the vessels of his house before you, and you and your lords, your wives and your women, have taken wine in them; and you have given praise to gods of silver and gold, of brass and iron and wood and stone, who are without the power of seeing or hearing, and without knowledge: and to the God in whose hand your breath is, and whose are all your ways, you have not given glory;

Then they made answer and said before the king, Daniel, one of the prisoners of Judah, has no respect for you, O King, or for the order signed by you, but three times a day he makes his prayer to God.

and I turned me unto God the LORD, for to pray and make mine intercession, with fasting, sack cloth and ashes.

"So now, O God, listen to the prayer of your servant and to his requests, and look with favor on your desolate sanctuary, for the sake of the Lord.

Turn your ear and listen, O God. Open your eyes and look at our desolation and at the city that is called by your name. We're not presenting our requests before you because of our righteousness, but because of your great compassion.

By smooth words he will turn to godlessness those who act wickedly toward the covenant, but the people who know their God will display strength and take action.

The wise, such as have taught others, shall glister as the shining of heaven: and those that have instructed the multitude unto Godliness, shall be as the stars, world without end.