Christ, precisely as the crucified one, is the Word that does not pass away,92 and He is the one who stands at the door and knocks at the heart of every man,93 without restricting his freedom, but instead seeking to draw from this very freedom love, which is not only an act of solidarity with the suffering Son of man, but also a kind of "mercy" shown by each one of us to the Son of the eternal Father. In the whole of this messianic program of Christ, in the whole revelation of mercy through the cross, could man's dignity be more highly respected and ennobled, for, in obtaining mercy, He is in a sense the one who at the same time "shows mercy"? In a word, is not this the position of Christ with regard to man when He says: "As you did it to one of the least of these...you did it to me"?94 Do not the words of the Sermon on the Mount: "Blessed are the merciful, for they shall obtain mercy,"95 constitute, in a certain sense, a synthesis of the whole of the Good News, of the whole of the "wonderful exchange" (admirable commercium) contained therein?
This exchange is a law of the very plan of salvation, a law which is simple, strong and at the same time "easy." Demonstrating from the very start what the "human heart" is capable of ("to be merciful"), do not these words from the Sermon on the Mount reveal in the same perspective the deep mystery of God: that inscrutable unity of Father, Son and Holy Spirit, in which love, containing justice, sets in motion mercy, which in its turn reveals the perfection of justice?