of the Church at Ephesus summoned.
When they came to him, he addressed them,
"now I know that none of you
to whom I preached the kingdom during my travels
will ever see my face again.
And so I solemnly declare to you this day
that I am not responsible for the blood of any of you,
for I did not shrink from proclaiming to you the entire plan of God."
-- Acts 20:17-27
St. Paul said to his disciple Timothy: "I remind you to rekindle the gift of God that is within you through the laying on of my hands" (2 Tim 1:6), and "If any one aspires to the office of bishop, he desires a noble task." (1 Tim 3:1) To Titus he said: "This is why I left you in Crete, that you amend what was defective, and appoint presbyters in every town, as I directed you" (Titus 1:5).
-- CCC 1590
Since the beginning, the ordained ministry has been conferred and exercised in three degrees: that of bishops, that of presbyters, and that of deacons. The ministries conferred by ordination are irreplaceable for the organic structure of the Church: without the bishop, presbyters, and deacons, one cannot speak of the Church (cf. St. Ignatius of Antioch, Ad Trall. 3,1).
-- CCC 1593