Question: Why do you say Holy Masses and administer the Sacraments during the vacancy of the Holy See?
Answer: The Church is always obliged to do this, because it is the order of the Divine Law of the New Testament.
There is neither explicit nor implicit prohibition in Canon Law to say Holy Masses and administer the Sacraments during the vacancy of the Holy See.
At all times of the vacancy of the Holy See the bishops and priests validly and lawfully administered the Sacraments in accordance with Divine Law of the New Testament: "Do this for a commemoration of me" (St. Luke 22:19) and "Going therefore teach ye all nations: baptizing them in the name of the Father, and of the Son, and of the Holy Ghost, teaching them to observe all things whatsoever l have commanded you: and behold I am with you all days, even to the consummation of the world." (St. Matthew 28:19-20)
Rt. Rev. John F. Sullivan in his book “THE VISIBLE CHURCH” says that the Catholic Church is a society instituted by Jesus Christ to teach men of God's truth and that this society has a government, i.e., the Hierarchy. Also, he says that through the Sacrament of Holy Orders the Hierarchy receives its power of offering public worship, of administering most of the Sacraments, and of instructing the faithful; and therefore it is known as the Hierarchy of Order.
There is unquestionable integrity between the Hierarchy of Order and its power of offering public worship, of administering the Sacraments, and of instructing the faithful, since the Hierarchy of Order has not been expired because of lack of the Hierarchy of Jurisdiction.
In a word, the Hierarchy of Order has the unquestionable power to say Holy Masses and administer the Sacraments during the vacancy of the Holy See.
However, if someone wants to appeal to Canon Law, he has a right to do that, but he will waste his time, because Canon Law does not say that there is no the Hierarchy of Order during the vacancy of the Holy See.
Here the quotations from the books follow:
THE VISIBLE CHURCH
by Rt. Rev. JOHN F. SULLIVAN, D.D.:
The Hierarchy. The Catholic Church is a society instituted by Jesus Christ to teach God's truth to men. Like other societies, it has a government. This is known as the hierarchy, from the Greek, meaning priestly rule.
All the grades of the hierarchy form the clergy, meaning "the chosen ones."
Through the sacrament of Holy Orders the hierarchy receives its power of offering public worship, of administering most of the sacraments, and of instructing the faithful; and it is therefore known as the Hierarchy of Order.
It possesses also the power of making laws and of ruling the faithful; and it is therefore known as the Hierarchy of Jurisdiction.
By divine institution, a hierarchy, consisting of Bishops, priests, and ministers was set up in the Church. Of the Bishops, one, the Bishop of Rome, was made by Christ Our Lord the head of the whole Church. The Bishop has the fullness of the priesthood and only he can perform certain acts, such as ordaining others to the Sacred Ministry. The priest cannot ordain nor, except in certain instances, Confirm. The Minor Orders are of ecclesiastical institution. (p.1)
The bishops form the episcopacy of our Church. Their authority comes from our Lord Himself, for He instituted not only the papacy but the episcopacy. (p.10) (1)
THE DOGMATIC DECREES OF THE COUNCIL OF TRENT:
Canon IV. If anyone saith that, by sacred ordination, the Holy Ghost is not given; and that vainly therefore do the bishops say: "Receive ye the Holy Ghost;" or that a character is not imprinted by that ordination; or that he who has once been a priest can again become a layman; let him be anathema.
Canon VI. If anyone saith that in the Catholic Church there is not a hierarchy by divine ordination instituted, consisting of bishops, priests and ministers; let him be anathema. (2)
The quotations from the Holy Scripture taken from: THE HOLY BIBLE PUBLISHED WITH THE APPROBATION OF THE CATHOLIC ARCHBISHOPS AND BISHOPS OF IRELAND. The Douay Version of the Old Testament of 1609, and with the Rhemish Version of the New Testament of 1582, Given at Dublin, May 4th, 1857.
(1) THE VISIBLE CHURCH
BY Rt. Rev. JOHN F. SULLIVAN, D.D.
A TEXT-BOOK FOR CATHOLIC SCHOOLS
Fifth Edition, Revised
P. J. KENEDY & SONS
PUBLISHERS TO THE HOLY APOSTOLIC SEE
NIHIL OBSTAT: ARTHURUS J. SCANLAN, S.T.D. Censor Librorum
IMPRIMATUR: PATRITIUS J. HAYES, D.D. Archiepiscopus Neo-Eboracensis
Neo-Eboraci die 5, Aprilis 1921.
Printed in U. S. A.
(2) DOGMATIC CANONS AND DECREES
AUTHORIZED TRANSLATIONS OF THE DOGMATIC DECREES OF
THE COUNCIL OF TRENT, THE DECREE ON THE IMMACULATE
CONCEPTION, THE SYLLABUS OF POPE PIUS IX, AND
THE DECREES OF THE VATICAN COUNCIL
BY THE DEVIN-ADAIR COMPANY
Nihil Obstat. REMIGIUS LAFORT, D.D., Censor
Imprimatur. +JOHN CARDINAL FARLEY, Archbishop of New York
June 22, 1912
THE DOGMATIC DECREES OF THE COUNCIL OF TRENT
On the Ecclesiastical Hierarchy and on Ordination