﴿ شَاكِرًۭا لِّأَنْعُمِهِ ۚ ٱجْتَبَىٰهُ وَهَدَىٰهُ إِلَىٰ صِرَٰطٍۢ مُّسْتَقِيمٍۢ ﴾

“[for he was always] grateful for the blessings granted by Him who had elected him and guided him onto a straight way.”

(Thankful for His bounties) thankful to Allah for the bounties He had bestowed upon him; (He chose him) He selected him for prophethood and Islam (and He guided him unto a straight path) He made him firm on an established path with which He is pleased, i.e. Islam.