John Wesley on Genesis 17:18

And Abraham said, O that Ishmael might live before thee! - This he speaks nor as desiring that Ishmael might be preferred before the son he should have by Sarah, but as dreading lest he should be forsaken of God, he puts up this petition on his behalf. The great thing we should desire of God, for our children, is, that they may live before him, that is, that they may be kept in covenant with him, and may have grace to walk before him in their uprightness. God's answer to this prayer, is an answer of peace. Abraham could not say he sought God's face in vain.