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

He showed his gratitude for the favours of God, who chose him, and guided him to a Straight Way.

Thankful for His bounties; He chose him and He guided him unto a straight path.

Grateful for His favours. He chose him and guided him on the right path.

[He was] grateful for His favors. Allah chose him and guided him to a straight path.