When Our Lord was starting the Church, so to speak, at the Last Supper, He took care to give to it the Four Marks He wished it to have. In His discourse afterwards in the Upper Room, He told the apostles He was offering eternal life to all flesh (read John xvii, 1-3) ; that the apostles themselves were His appointed witnesses and workers (John xv, 16; xv, 27); and He prayed that His disciples should be all one (John xvii, ii ; Xvii, 20-21); and that they should be made holy in the truth (John xvii, 17-19), getting their holy life from His as the branches from the Vine (John xv, 4-5).
If there is a true Church of Christ still on earth, we must expect it to show those four marks still.
– Rev. F.H. Drinkwater, Catechism Stories Part I: the Creed (1939)