1. As enjoined by Saint Peter and Saint Paul, early Christians terminated any reading of Scriptures with a kiss.
2. At High Mass the celebrant kisses the altar, and presents his left cheek to the deacon's, saying Pax tecum (peace be with you); the deacon conveys the salute to the sub-deacon, thence to the other clergy. This is called the Kiss of Peace.
3. The celebrant kisses the altar nine times during Mass as a symbol of respect.
4. Kissing the pope's foot is a salute of respect in solemn papal Mass, at the "veneration" of the pope by cardinals, and in a private audience.
5. A bishop kisses those he has just ordained priests.