﴿ يَٰقَوْمَنَآ أَجِيبُوا۟ دَاعِىَ ٱللَّهِ وَءَامِنُوا۟ بِهِۦ يَغْفِرْ لَكُم مِّن ذُنُوبِكُمْ وَيُجِرْكُم مِّنْ عَذَابٍ أَلِيمٍۢ ﴾

““O our people! Respond to God’s call, and have faith in Him: He will forgive you [whatever is past] of your sins, and deliver you from grievous suffering [in the life to come].”

(O our people! respond to Allah's summoner) Muhammad (pbuh) in his call for belief in Allah's divine Oneness (and believe in Him. He will forgive you some of your sins) Allah will forgive you the sins you committed in the time of ignorance (and guard you from a painful doom) and save you from a painful torment.