The Jewish insight into prayer considers that we don’t always pray as we ought. But, in a group,
the benefit of each spreads to the whole group. So, when I am not praying with the right emphasis, someone else probably is, and the merit of the prayer spreads to the entire “body” of those in prayer.
It’s an elegant insight into the effort we should each should put into prayer to benefit each other. In the Catholic sense, when I say the Hail Mary and say “pray for us sinners” my intention is to pray for the whole world – “us sinners” Same, too, with the Lord’s prayer. How wonderful that the Church has offered those prayers for our participation.