'Oh' in the Bible

Gideon said to him, "Oh, my lord, if Yahweh is with us, why then has all this happened to us? Where are all his wondrous works which our fathers told us of, saying, 'Didn't Yahweh bring us up from Egypt?' But now Yahweh has cast us off, and delivered us into the hand of Midian."

Then Manoah entreated Yahweh, and said, "Oh, Lord, please let the man of God whom you did send come again to us, and teach us what we shall do to the child who shall be born."