Pride slays thanksgiving, but an humble mind is the soil out of which thanks naturally grow. A proud man is seldom a grateful man, for he never thinks he gets as much as he deserves. A thankful heart is not only the greatest virtue, but the parent of all other virtues. Jesus, in this passage, asked, where the thanksgiving was. The Savior is grieved at the revelation of gross ingratitude on the part of the other nine lepers, who do not glorify and thank God, but as so selfishly taken up by their cure that the do not even take the trouble of turning back to him out of gratitude as the Samaritan did.
Some people always sigh in thanksgiving.
Elizabeth Barrett Browning. And some times the people who should be most thankful are the least thankful. Much of your spirituality will be typified by your thankfulness. People, who view themselves as debtors to grace, are incurably thankful. If we realize that we do not deserve eternal life, that impacts the way we view blessedness in this life.