Ss Cyril and Methodius: "my brother’s keeper"

... offer to God a sacrifice of praise.

-- Ps 50:1 and 8, 16bc-17, 20-21

From the Sermon on the Mount onwards, Jesus insists on conversion of heart: reconciliation with one's brother before presenting an offering on the altar, love of enemies, and prayer for persecutors, prayer to the Father in secret, not heaping up empty phrases, prayerful forgiveness from the depths of the heart, purity of heart, and seeking the Kingdom before all else. This filial conversion is entirely directed to the Father.

-- CCC 2608