In this basilica and the adjoining palace were held, from the 4th to the 16th centuries, more than twenty-five councils, five of which were ecumenical. Holy Orders were conferred there, penitents were reconciled, catechumens wee baptized on Easter Day, and as neophytes they came there in procession during the whole octave.
The Stational mass is held at St. John Lateran on the first Sunday in Lent, Palm Sunday, Rogation Tuesday, Maundy Thursday, Easter Eve, Saturday in Albis, and on the eve of Pentecost.
The church was rebuilt and consecrated anew by Benedict XIII in 1726, and the commemoration of this consecration was fixed, as that of the first church, on 9th November.
Terríbilis est locus iste: hic domus Dei est et porta coeli: et vocábitur aula Dei. * Quam dilécta tabernácula tua, Dómine virtútum! concupíscit, et déficit ánima mea in átria Dómini.
Terrible is this place: it is the house of God, and the gate of heaven; and it shall be called the court of God. * How lovely are Thy tabernacles, O Lord of Hosts! my soul longeth and fainteth for the courts of the Lord.
(Genesis 28:17 and Psalm 83:2-3 from the Introit of Mass)
Deus, qui nobis per síngulos annos hujus sancti templi tui consecratiónis réparas diem, et sacris semper mystériis repaeséntas incólumes: exáudi preces pópuli tui, et praesta; ut, quisquis hoc templum benefícia petitúrus ingréditur, cuncta se impetrásse laetétur.O God, who every year dost renew the day of the consecration of this Thy holy temple, and continuest to bring us in safety to Thy sacred mysteries, graciously hear the prayers of Thy people, and grant that all who enter this temple to implore Thy blessings, may rejoice in obtaining whatsoever they ask.
The Lord hath made this tabernacle * his holy place, for this is the house of the Lord, wherein we stand before his presence and cry unto him, and whereof it is written: My Name shall be there, saith the Lord.
(Magnificat Antiphon from 1st Vespers)
Blessed City, heavenly Salem,
Vision dear of peace and love,
Who, of living stones upbuilded,
Art the joy of heaven above,
And, with Angel cohorts circled,
As a bride to earth dost move!
(From the hymn, Caelestis urbs Jerusalem)
The Catholic Encyclopaedia on the Basilica of St John Lateran: http://www.newadvent.org/cathen/09014b.htm