d.] Hence the Apostle employs the term "priests"
in reference to both, when he says (1 Tim. 5:17): "Let the priests
that rule well be esteemed worthy of double honor"; and again he uses
the term "bishops" in the same way, wherefore addressing the priests
of the Church of Ephesus he says (Acts 20:28): "Take heed to
yourselves" and "to the whole flock, wherein the Holy Ghost hath
placed you bishops, to rule the church of God."

But as regards the thing signified by these terms, there was always a
difference between them, even at the time of the apostles. This is
clear on the authority of Dionysius (Eccl. Hier. v), and of a gloss
on Luke 10:1, "After these things the Lord appointed," etc. which
says: "Just as the apostles were made bishops, so the seventy-two
disciples were made priests of the second order." Subsequently,
however, in order to avoid schism, it became necessary to distinguish
even the terms, by calling the higher ones bishops and the lower ones
priests. But to assert that priests nowise differ from bishops is
reckoned by Augustine among heretical doctrines (De Heres. liii),
where he says that the Arians maintained that "no distinction existed
between a priest and a bishop."

Reply Obj. 2: Bishops have the chief cure of the sheep of their
diocese, while parish priests and archdeacons exercise an inferior
ministry under the bishops. Hence a gloss on 1 Cor. 12:28, "to one,
helps, to another, governments [*Vulg.: 'God hath set some in the
church . . . helps, governments,' etc.]," says: "Helps, namely
assistants to those who are in authority," as Titus was to the
Apostle, or as archdeacons to the bishop; "governments, namely
persons of lesser authority, such as priests who have to instruct the
people": and Dionysius says (Eccl. Hier. v) that "just as we see the
whole hierarchy culminating in Jesus, so each office culminates in
its respective godlike hierarch or bishop." Also it is said (XVI, qu.
i, can. Cunctis): "Priests and deacons must all take care not to do
anything without their bishop's permission." Wherefore it is evident
that they stand in relation to their bishop as wardens or mayors to
the king; and for this reason, just as in earthly governments the
king alone receives a solemn blessing, while others are appointed by
simple commission, so too in the Church the episcopal cure is
conferred with the solemnity of consecration, while the archdeacon or
parish priest receives his cure by simple appointment