In the Qur'an we find the following two statements:

39:4

Had Allah wished to take to Himself a son,
He could have chosen whom He pleased out of those whom He doth create:
but Glory be to Him! (He is above such things.)
He is Allah, the One, the Irresistible. (Yusuf Ali)

If Allah had willed to choose a son,
He could have chosen what He would of that which He hath created.
Be He Glorified! He is Allah, the One, the Absolute. (Pickthall)

6:101

Wonderful Originator of the heavens and the earth;
How can He have a son when He has no consort?
He created all things, and He hath full knowledge of all things.

Sura 39:4 and 6:101 agree on the actuality, that Allah does not have a son, but they contradict each other in the issue of ability or possibility.

Sura 39:4 clearly states that God could have taken Himself a son from among his creation, i.e. without the necessity of a consort to father such a son. But Sura 6:101 clearly rejects the same idea as a logical impossibility.

Contradictions in the Qur'an
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