'O God' in the Bible

We give thanks to God at all times for you all, making mention of you in our prayers;

for they themselves report, concerning us, what manner of entrance we had to you, and how ye turned to God from idols to serve a living and true God,

And, for this reason, we also give thanks to God without ceasing, that, having received the word of God which ye heard from us, ye received it, not as the word of men, but, as it truly is, the word of God, which also is working in you who believe.

For what thanksgiving can we render again to God concerning you for all the joy wherewith we rejoice on your account before our God;