"Lord God, fountain of all mercy, look upon our gifts on this feast of St. Joseph. Let our sacrifice become the protection of all who call on you…." (Offertory Prayer on the feast of St. Joseph the Worker)
God our Father is the fountain of all mercy. O that I would remember this at the moment of need.
The gifts we bring up to the altar, bread and wine, fruits of our labor represent our sacrifice. We join this with the one sacrifice of Jesus Christ and ask the Father and fountain of all mercy for our protection from evil and all who call upon Him.