Reverence
When you enter a Church, if the tabernacle is visible (i.e. hasn’t been placed in a separate room ), look for the red lamp near it. If it is lit, that means the Jesus is present in the tabernacle. If not, the tabernacle is empty and no genuflection is necessary.
If the Blessed Sacrament is present, and if you are just going to walk around the church but not sit down (i.e.: you are there to do the stations of the cross), you should genuflect on one knee when passing directly in front of the altar. If you are going to sit in a pew, genuflect on one knee before entering and leaving.
During the Passion of Christ, Roman soldiers knelt with their left knee to Jesus in mockery. Catholics should remember to always genuflect with their right knee as a sign of respect to the Holy Eucharist.
