"Our bread": the Father who gives us life cannot not but give us the nourishment life requires - all appropriate goods and blessings, both material and spiritual. In the Sermon on the Mount, Jesus insists on the filial trust that cooperates with our Father's providence. He is not inviting us to idleness, but wants to relieve us from nagging worry and preoccupation. Such is the filial surrender of the children of God:
To those who seek the kingdom of God and his righteousness, he has promised to give all else besides. Since everything indeed belongs to God, he who possesses God wants for nothing, if he himself is not found wanting before God.
Source: Catechism of the Catholic Church (Vatican.va)