Monotheism: No offspring allowed

Muhammad did not agree with as many sexual notions that, for example, the Greeks did.  Muhammad did not agree with the existence of Jesus because Jesus is believed to be the offspring of God.  Being the offspring of God? Not likely, according to Muhammad.  Even after claiming the three most famous goddess as Allah's daughters, Muhammad took it back instantly.  His disagreement with grand holy figures having offspring help a high value.  Is this because God is too mighty to have children or because he lacks the power to?