'O Lord My God' in the Bible

But look to the prayer of thy servant and his supplication, O LORD my God, to give an ear unto the voice and prayer which thy servant prayeth before thee this day,

and called unto the LORD and said, "O LORD my God, hast thou been so evil unto the widow with whom I sojourn, that thou hast slain her son?"

And he stretched himself upon the lad three times, and called unto the LORD and said, "O LORD my God, let the lad's soul come into him again."