Round squares can't exist. Heavy rocks can. Given an infinite amount of time and space, only things that are possible will occur, and even the most vastly powerful beings in existance can only do what is possible. Omnipotency is something differant. It means without limitations.
Married bachelors only exist in the opinion of zealots when gay people get married.
So because heavy rocks are real, and one's weight capacity is real... what exactly are you saying? That God can't make heavy rocks... or that God has a finite number of pounds he can lift? There is only one possibility here. (Hint, its none-of-the-above)
The reason why this question makes faith-drenched minds run and hide is because is is absolute 100% logical proof that there is no such thing as omnipotency. Omnipotency is impossible, because in order for it to exist, it would require direct contradictions to exist at the same time... like round squares. Nothing can do "anything" because the existance of some things cancel out the possibility of the existance of other things. i.e. Since circles & squares both exist and are defined and given identity by their retrospective shapes, we know that round squares cannot exist with certainty. For such things to exist would require an existance without physical laws. God himself claims he has brought order, or laws into existance... so since these exist, he has made himself into a logical falicy.
In order to remain "faith-minded" without a direct confrontation between faith and reason, you have to dodge this question with silly answers that don't address the question, or else make absurd and incorrect assertions about the question or questioner, such as "Thats a logical falicy!" No.... its not. Its called a trick question. Meaning that the answer is to be derived from outside the scope of the inquary.
Omnipotency and round-squares are logical falicies, because they cannot exist in a logical universe. A question asking if a limitless being can do two actions that rule each other out "is" possible. Its no differant than asking how much larger does the government need to grow in order to end corruption, or how much sugar one needs to put in coffee before its not sweet any longer.
Your only viable escape from this question "if" you decide to confront it head on, rather than dodge it, is to believe that god can do impossible things... such as make a rock too big to lift AND lift it at the same time. You may as well toss whatever scrap remains of your human reason when you decide to believe in impossible things, because the battle is lost, and you are mentally broken. Congradulations, you're now a life-long chrisitian completely immune to logic and reason. Facts will bounce off you like .22 shells off a sherman tank.
If you commit to this question with reason, you'll soon know what sort of person you are. Some human minds simply cannot abandon reason once that collision between faith and reason occurs, and their faith is doomed the moment they decide to truly commit to this. This question, and those like it are your key to mental liberty. Most are not, or may never be ready for that confrontation and will only dodge. The rest will commit and crush their reason forever, becoming zealots.
Of course the easier answer would be... he's an ego maniac that wants his serfs to think he's limitless. However he mucked that up when he gave some of us a working brain. But relax... im sure God wants to be surrounded in heaven only with people who cannot grasp logic, never question authority and will condone any evil (torture, genocide) so long as someone reeeeeeally powerful is doing it.
We mustn't believe in impossible things. Even a little girl named Alice understood this.