Have you ever attended Mass angry at a member of your immediate family? And then you have to offer them peace! Thankfully, the sign of peace comes toward the end of the liturgy and I have usually calmed down somewhat by that point. Still, extending a greeting and saying those words “Peace be with you” forces the issue. We need to be reconciled to approach the altar. We need to forgive and be forgiven.
With the exception of the above scenario, the sign of peace is part of Mass that I never really thought about all that much. Most weeks, I simply extend a friendly greeting to those near me, and then Mass continues. Pathway to Our Hearts: A Simple Approach to Lectio Divina With the Sermon on the Mount , a new book by Archbishop Thomas Collins, invited me to give it greater consideration.
Collins examines the Sign of Peace in the context of how it relates to Matthew 5:23-24: “Therefore, if you bring your gift to the altar, and there recall that your brother has anything against you, leave your gift there at the altar, go first and be reconciled with your brother, and then come and offer your gift.” He writes:
Before we receive our blessed Lord himself, we say “Peace be with you.” . . . We offer the peace of Christ. And if somewhere in the church there’s someone who has made me angry, or who has done something that has hurt me, or if I have wronged someone, then I start climbing over the pews to say “Peace be with you.” Now, that might be more than is necessary, like going to confession in public. It’s sufficient and symbolic enough to turn and say to whoever is nearby, “Peace be with you; peace be with you.” . . .
Giving the sign of peace could be a very sublime experience of what our Lord is talking about in this verse. We turn to the person, and we could be thinking, “I can’t stand you. Your personality rubs me the wrong way. Your political views are outrageous. Your taste in clothes is abominable. I would not want to go on a trip with you.” But then we say aloud: “The peace of Christ be with you.” That’s the heart of it all.
Obviously, then, the sign of peace is meant to be much more than just a polite demonstration to those near to us at Mass. As with everything else in the liturgy, it has great purpose and meaning. In the Tridentine Rite, the sign of peace is only extended among the clergy and sacred ministers. The Novus Ordo brought back the practice of the early Church of sharing the kiss of peace among the faithful at the liturgy.
In St. Augustine’s Sermon 227 he refers to this kiss of peace: “After this, the ‘Peace be with you’ is said, and the Christians embrace one another with the holy kiss. This is a sign of peace; as the lips indicate, let peace be made in your conscience, that is, when your lips draw near to those of your brother, do not let your heart withdraw from his.”
In Sacramentum Caritatis, Pope Benedict XVI instructs, “By its nature the Eucharist is the sacrament of peace. At Mass this dimension of the Eucharistic mystery finds specific expression in the sign of peace. Certainly this sign has great value (cf. Jn 14:27). In our times, fraught with fear and conflict, this gesture has become particularly eloquent, as the Church has become increasingly conscious of her responsibility to pray insistently for the gift of peace and unity for herself and for the whole human family. Certainly there is an irrepressible desire for peace present in every heart.”
Therefore, the sign of peace we offer to those near to us is both a literal and symbolic action. We need to be at peace with those with whom we share our lives, and isn’t it true that sometimes those are the hardest people to be at peace with? During the Mass, we reach out to them and wish them a heartfelt “Peace be with you.” Peace in our world needs to start with peace in our own homes. 
The peace we extend to other members of the congregation is largely symbolic. While there are certainly exceptions, most likely we have not offended the person sitting in the pew behind or in front of us in any manner, yet, by offering peace to them, we are offering our peace to our greater community and to the world at large.
In a world in such desperate need of peace, the sign of peace is extremely important. The next time you extend your hand in friendship at Mass, I invite you to think more deeply about what that symbol means .