"Nothing is so strong as prayer; nothing is so useful for all good things." St. John Chrysostom

The prayer he is talking about is not the prayer of the lips but the prayer of the heart.  It is easy to say words. It is more meaningful to be thoughtful and intentional when we pray. It is easy for one to say I love you. But if those words do not come from the depth of our heart, then they have no meaning. God sees the heart of the person who prays. He knows our inner thoughts. He is not impress with our words. What pleases him is what is behind our words.