PORTA SANTA. — A walled-up door found in Rome, in the patriarchal basilicas of S. Pietro in Vaticano, S. Giovanni in Laterano, S. Paolo fuori le mura, and S. Maria Maggiore all'Esquilino, beside the main entrance, which is opened on the occasion of the celebration of the universal Jubilees.
The P. S. of the Vatican Basilica is opened by the Supreme Pontiff on Christmas Eve, which immediately precedes the Holy Year (v. GIUBILEO), with highly distinctive and special ceremonies, during which the Supreme Pontiff strikes the center of the door three times with a golden hammer, intoning the verses: Aperite mihi portas institutae. Introibo in domum tuam, Domine. Aperite mihi portas, quoniam vobiscum Deus. At the same time, three cardinals legates a latere proceed to open the other P. S. On the eve of the following Christmas, the four P. S. are closed in the reverse ceremony.

(photo Enc. Catt.)
PORTA SANTA - Pope Clement X opens the P. S. for the Jubilee of 1673, bas-relief by Leonardo Reti. The cardinal holding the mantle is the cardinal-nephew Galeazzo Altieri. Detail of the monument to Clement X - Rome, basilica of S. Pietro.
De' Giubilei universali celebrati negli Anni Santi, Rome 1675, p. 17). The opening of the P. S. in the celebration of the Holy Years has an undeniable reference to the various events which, according to the ancient law, are said to have taken place before the gates of the temple, and to the fact that, as s. Cipriano states, the doors of the churches were closed to sinners (Ep., 31). There is certain information concerning the opening of the P. S. and the related rite on Christmas Eve of 1449 (Jubilee year 1450), under the pontificate of Niccolò V (cf. Pastor, I, p. 429).
To obtain the indulgence of the Jubilee, it is not necessary to enter or leave through the P. S. (S. Penitenz. Apost., Monito of 17 Sept. 1949, in AAS, 41 [1949], p. 516, XII, 4°).