Gratitude is more than a mental exercise, more than a formula of words. We cannot be satisfied to make a mental note of things which God has done for us and then perfunctorily thank Him for favors received.
To be grateful is to recognize the love of God in everything He has given us — and He has given us everything. Every breath we draw is a gift of His love, every moment of existence is grace, for it brings with us immense graces from Him. Gratitude therefore takes nothing for granted, is never unresponsive, is constantly awakening to new wonder, and to praise of the goodness of God. For the grateful person knows that God is good, not by hearsay but by experience. And that is what makes all the difference… Gratitude is therefore the heart of the Christian life.