[@Bishop]

All powerful in the sense that he has infinite energy and infinite control over that energy. In a sense, you could even say that he can do anything at all, but the problem is that a blanket absolute statement phrased that way leads to all sort of logical errors (i.e. "Can God create a square circle?"). So if you want to define omnipotent as "Able to do anything," you have to be extremely careful not to create questions with internal inconsistencies. For example, the square circle question is grammatically correct, but there's no real meaning to it because you asked two definitions to contradict each other. The same kind of error applies to God creating a rock too heavy to lift. By definition, God could lift anything he wanted because of infinite physical strength, so attempting to define a rock as too heavy for an omnipotent being is mathematically equivalent of asking for 5 to be considered a greater value than infinity, which is another absurd conclusion. In the same way, attempting to define God as sinful contradict the definition of the Christian God (because sin is defined as anything counter to God's nature). So you end up attempting to ask God to do something that is defined as something God would not do. In discrete mathematics, you're looking at this issue:
A = God;
B = Sin;
A∩B = 0;
∃x∈A|x∈B;

Which is not possible because if x∈A, then x∉B
Mathematically speaking, you end up with an impossible conclusion (you can read that as essentially saying that there exist an element x in set A so that x is also contained within set B), because there is zero overlap between set A and set B (A∩B = 0). So not only is it fine if we define omnipotent as infinite energy, but it is also fine if we used your definition because anything that would be self-violating in the idea of omnipotence is a logical error. It's just easier for people to say "Omnipotence means he can do anything" rather than define it like I did or go through the math to prove that it is not actually an illogical statement.