The answer
The priest kisses the altar in thanksgiving and claps with joy thanking the Lord for allowing us to celebrate the Divine Liturgy and partaking of the Holy Eucharist. As he encircles the altar he recites Psalm 47 (46) "Oh, clap your hands, all you peoples! Shout to God with the voice of triumph!"Answered by His Eminence Metropolitan Youssef (opens in a new tab)