"What sign can u do that we may see & believe in u?" The people asked Christ for a sign to prove to them that He was sent by God. They cited manna that fell from heaven daily at Moses' time.
He gave them no sign at that time but He declared, "I AM the Bread of Life."
At the Last Supper, Christ gave the world THE Sign, the Eucharist, the Bread of Life.
A sacrament is the visible sign of invisible grace. The Eucharist is Christ's continuing incarnation, His visible flesh in the world. It's the spiritual food that increases Christ's presence in us. Like St Stephen (1st Reading) fear of death wont stop us from following Christ.
As we pray for the reopening of churches, lets open our hearts & be Christ's sacraments to our neighbors.