Responsorial Psalm  (Psalm 98)
R. All the ends of the earth have seen the saving power of God.
All the ends of the earth have seen the salvation by our God.
Sing joyfully to the LORD, all you lands; break into song; sing praise.
R. All the ends of the earth have seen the saving power of God.
https://bible.usccb.org/bible/readings/010224.cfm
Like Easter, Christmas has produced its share of music praising the “saving power of God.” In Latin America we have an abundance of Christmas carols (villancicos). As the Psalm tells us: “Break into song; sing praise!” Today we remember two of the Cappadocian Fathers, Saint Basil (330-379) and his friend, Saint Gregory (329-390). The Liturgy of Saint Basil is still celebrated in the Eastern Rites of the Church and is echoed in the Fourth Eucharistic Prayer.