The Third Sunday after Easter
ALMIGHTY God, who showest to them that are in error the light of thy truth, to the intent that they may return into the way of righteousness; Grant unto all those who are admitted into the fellowship of Christ's Religion, that they may avoid those things that are contrary to their profession, and follow all such things as are agreeable to the same; through our Lord Jesus Christ. Amen.
Source of Collect: Sacramentary of Leo, Bishop of Rome [440-461AD]. The Vigil of Easter was the traditional time for Baptism, and this collect speaks to the newly baptized "all those who are admitted into the fellowship". One had to be baptized to be present during the Eucharist. Christiana professione censentor
1 Samuel ii. 1b, Psalm 113, 1 St. Peter ii. 11. St. John xvi. 16.
Homily of John Chrysostom on the Gospel
A little while, and ye shall not see me: and again, a little while, and ye shall see me, because I go to the Father.
IN HOC SIGNO VINCES - TIME DEUM ET OPERARE IUSTITIAM