It becomes a knee-jerk reaction for Catholics to genuflect before sitting down, whether it’s in Church, in the movie theater, or even at the park bench. We only need to do it in Church, but why do we do it?
The Catechism tells us that genuflecting is “a reverence made by bending the knee, especially to express adoration of the Blessed Sacrament.” Jesus is really, truly, and substantially present in the Eucharist, which is reserved in the tabernacle. We are entering His space, and our whole beings are drawn to be with Him and worship Him. Just as, in the Middle Ages, each person who entered the throne room of the king would bend their knee or bow in his presence, so we bend our knee in the presence of the King of the Universe as we come before His humble throne that is the tabernacle. The king’s subjects showed honor, respect, and admiration when they bent their knees before their king. We show honor, respect, and admiration to Jesus, along with love and adoration, when we humble ourselves before Him.
This includes our bodies; we do certain actions and make certain gestures to show our honor, love, and worship to Jesus. Bending our knees before Jesus in the Blessed Sacrament fulfills what St. Paul tells us, that “at the name of Jesus every knee should bend” (Philippians 2:10). The name of Jesus is the person of Jesus, Who is present in the tabernacle. We bend our knee in His presence because He is God and we are not. He is our Savior, and we are the saved. He is most merciful, and we are in need of the mercy He gives. We humble ourselves by genuflecting, and Jesus humbles Himself by coming to us.
You might notice, though, that the priest, deacon, and altar servers only genuflect as they enter and leave the sanctuary; for the rest of the Mass they bow to the altar. This is because the focal point of the Mass is not the tabernacle, but the altar. The Mass is the re-presentation of the sacrifice of Jesus on the altar of the Cross, so during the Mass we focus on the altar. The altar is not the Real Presence of Jesus, however, but a symbol of Jesus and His sacrifice. We make this distinction in the Mass by bowing to the altar (the symbol) but genuflecting to the tabernacle (the Real Presence). This also happens in those churches that keep the tabernacle in a separate chapel and not in the main sanctuary. In this case, everyone bows to the altar before entering and leaving their pews. We have the tabernacle in the sanctuary here at St. Hubert, and so we genuflect.
Jesus is Lord, and we are not. As we enter the Church, we are entering His space. He opens this space to us and receives us with great love and joy. Genuflecting to the presence of our Lord and King as we enter and exit the pews keeps us humble as we enter into the joy of our Lord.