Q. Why do we always begin the Mass with the sign of the Cross and end the Mass with the sign of the Cross?
A. It is simply said that each Mass is a Thanksgiving Banquet that we are all welcome to join. As we say "hi" and "bye" to the host of the banquet when we come to the banquet, we say "hi" and "bye" to God at the beginning of the Mass and at the end of the Mass with the sign of the cross. Thanks for the question.