Gratitude springs from the heart for a favour received. The quality of being thankful is essential for genuine praise of Allah and appreciation of His bounties. The Holy Prophet Muhammad (sa) used to say that if a person is not thankful to his fellow human beings for their good deeds done to him, he is not thankful to God. Such a person is not in the habit of acknowledging favours or this sentiment has gone cold in him.
The Holy Prophet Muhammad (sa) taught his ummah [people] the manner of appreciation of God’s favours. Hazrat Uthman (sa) relates that the Holy Prophet Muhammad (sa) said, ‘Whosoever receives a favour from someone should say, جَزَاكَ اللهُ خَيْرًا meaning, “May Allah give you the best reward for it”. By saying this he has discharged his obligation of thankfulness.”’
He used to say, ‘If someone has done good to you, repay him and if you do not have the capacity to repay, at least pray for that person to the extent that you are sure of repaying him fully.’
Muhammad (sa) – The Perfect Man (Qadian, India: Nazarat Isha’at, 2015), 117.