﴿ رَّبُّكُمْ أَعْلَمُ بِكُمْ ۖ إِن يَشَأْ يَرْحَمْكُمْ أَوْ إِن يَشَأْ يُعَذِّبْكُمْ ۚ وَمَآ أَرْسَلْنَٰكَ عَلَيْهِمْ وَكِيلًۭا ﴾

“Your Sustainer is fully aware of what you are [and what you deserve]: if He so wills, he will bestow [His] grace upon you; and if He so wills, He will chastise you. Hence, We have not sent thee [unto men, O Prophet,] with the power to determine their fate,”

Your Lord knows you best. If He will He will have mercy on you by way of granting you repentance and faith or if He will for you to be chastised He will chastise you by having you die in disbelief. And We did not send you to be a guardian over them and so compel them to embrace faith — this was revealed before the command to fight them.