Many Christians claim that God can do EVERYTHING and ANYTHING he pleases. The Muslim obviously agrees with this statement. However, the Christian will then claim that God can become a man.
This is where the Muslim disagrees with the Christian and the Muslim has to clarify something which should be apparent to the Christian. God can do sensical things and can’t not do nonsensical things.
For example, can a square-triangle or a triangle-square exist? No. There is no such a thing as four-sided, three-sided figure or a three-sided, four-sided figure. It is a nonsensical statement.
Likewise, is there such a thing as a man-god , or god-man? The answer is no, it is a nonsensical statement.
Now this is not a limitation on God , but this is a limitation on the claimant’s reasoning and intellect.