How Do I Answer the 'Rock Too Heavy to Lift' Challenge?
An atheist posed the question to me, "If God is all powerful, can he create a rock too heavy to lift?" How do I reply to that?
God’s omnipotence extends to all things that do not involve a logical contradiction. Since the idea of God creating a rock that is too heavy for him to lift involves a logical contradiction, it’s not subject to his omnipotence. This doesn’t count against his omnipotence anymore than the claim that God can’t make a square circle.
The reason this idea involves a logical contradiction is that it claims God is all-powerful (inasmuch as he creates the rock) and not all-powerful (inasmuch as he can’t lift the rock) in the same respect at the same place and time. Since this is a violation of the principle of non-contradiction, it cannot be.
Therefore, it’s not due to a lack of God’s power that he can’t create a rock that is too heavy for him to lift. It’s due to the impossibility of such a state of affairs.