The Jews used to say that if a man came to his wife in her vagina from behind, the child would be cross-eyed. So Allah, glorified be He, revealed, "Your women are a tilth for you, so come to your tilth however you wish" [Baqarah 2:223].
حدثنا سهل بن أبي سهل وجميل بن الحسن قالا حدثنا سفيان بن عيينة عن محمد بن المنكدر أنه سمع
كانت يهود تقول من أتى امرأته في قبلها من دبرها كان الولد أحول فأنزل الله سبحانه {نساؤكم حرث لكم فأتوا حرثكم أنى شئتم}
Bukhari narrated it in the Book of Tafsir, in the chapter on "Your wives are a tillage for you, so come to your tillage when or how you will" [Baqarah 2:223], etc, hadith no. 1435, from the narration numbered 4528, and Muslim narrated it in the Book of Nikah, in the chapter on the permissibility of having intercourse with one's wife in her front, from Sufyan, with the same wording.