pre-Islamic customs of slaying children

وَكَذَٰلِكَ زَيَّنَ لِكَثِيرٍ مِّنَ ٱلْمُشْرِكِينَ قَتْلَ أَوْلَـٰدِهِمْ شُرَكَآؤُهُمْ لِيُرْدُوهُمْ وَلِيَلْبِسُوا۟ عَلَيْهِمْ دِينَهُمْ ۖ وَلَوْ شَآءَ ٱللَّهُ مَا فَعَلُوهُ ۖ فَذَرْهُمْ وَمَا يَفْتَرُونَ

In the same way, their idols have induced many of the pagans to kill their own children, bringing them ruin and confusion in their faith: if God had willed otherwise they would not have done this, so [Prophet] leave them to their own devices.

قَدْ خَسِرَ ٱلَّذِينَ قَتَلُوٓا۟ أَوْلَـٰدَهُمْ سَفَهًۢا بِغَيْرِ عِلْمٍ وَحَرَّمُوا۟ مَا رَزَقَهُمُ ٱللَّهُ ٱفْتِرَآءً عَلَى ٱللَّهِ ۚ قَدْ ضَلُّوا۟ وَمَا كَانُوا۟ مُهْتَدِينَ

Lost indeed are those who kill their own children out of folly, with no basis in knowledge, forbidding what God has provided for them, fabricating lies against Him: they have gone far astray and have heeded no guidance.