﴿ وَإِن جَٰدَلُوكَ فَقُلِ ٱللَّهُ أَعْلَمُ بِمَا تَعْمَلُونَ ﴾

“And if they [try to] argue with thee, say [only]: “God knows best what you are doing.””

And if they dispute with you in the matter of religion say ‘God knows best what you do and will requite you for it — this was revealed before the command to fight them.