When we say to people, 'I will pray for you,' we make a very important commitment. The sad thing is that this remark often remains nothing but a well-meant expression of concern. But when we learn to descend with our mind into our heart, then all those who have become part of our lives are led into the healing presence of God and touched by him in the center of our being. We are speaking here about a mystery for which words are inadequate. It is the mystery that the heart, which is the center of our being, is transformed by God into his own heart, a heart large enough to embrace the entire universe. Through prayer we can carry in our heart all human pain and sorrow, all conflicts and agonies, all torture and war, all hunger, loneliness, and misery, not because of some great psychological or emotional capacity, but because God's heart has become one with ours.
From the heart arise unknowable impulses as well as conscious feelings, moods, and wishes. The heart, too, has its reasons and is the center of perception and understanding. Finally, the heart is the seat of the will: it makes plans and comes to good decisions. Thus the heart is the central and unifying organ of our personal life. Our heart determines our personality, and is therefore not only the place where God dwells but also the place to which Satan directs his fiercest attacks. It is this heart that is the place of prayer. The prayer of the heart is a prayer that directs itself to God from the center of the person and thus affects the whole of our humanness.
Hypocrisy is wretched because the hypocrite says with his tongue what is not in his heart. He wrongs his tongue and oppresses his heart. But if the heart is sound, the condition of the tongue follows suit. We are commanded to be upright in speech, which is a gauge of the heart's state.