All are assembled inside the church for the prayer.
Everyone is in the church.
Everyone is assembled in church, they are there for prayer.
exists x2 x3.(n_prayer(x3) & n_church(x2) & all x1.(n_thing(x1) -> exists e1.(for(e1,x3) & inside(e1,x2) & Theme(e1,x1) & v_assemble(e1))))
exists x2.(n_church(x2) & all x1.(n_person(x1) -> exists p1.in(x1,x2)))