﴿ إِنَّكَ إِن تَذَرْهُمْ يُضِلُّوا۟ عِبَادَكَ وَلَا يَلِدُوٓا۟ إِلَّا فَاجِرًۭا كَفَّارًۭا ﴾

“for, behold, If Thou dost leave them, they will [always try to] lead astray those who worship Thee, and will give birth to nothing but wickedness and stubborn ingratitude.”

Assuredly if You leave them they will lead Your servants astray and will beget only disbelieving profligates fājir and kaffār derive respectively from yafjuru and yakfuru he said this on account of the mentioned revelation that had been given to him.