The Quran repeatedly mentions shukr, or gratitude. According to the Quran, shukr is a great form of worship. Rather, it is the greatest form of worship. Shukr means acknowledgment. Shukr is the highest or ultimate extent of positive thinking. That is, you should lead your life in this world with the realization that God has bestowed innumerable blessings upon you, and you have to acknowledge Him for that. Shukr is the greatest positive phenomenon. There can be no other positive phenomenon greater than shukr. To lead life being conscious of God's blessings, acknowledging God every moment, thanking God every moment. This is shukr.