7 We have been no less consoled to know that with spontaneous generosity a fund has been created for the erection of a church in Rome to be dedicated to our saintly predecessor and patron, Eugene I. At this temple, to be built by the wish and through the liberality of all the faithful, will be a lasting memorial of this happy event, so We desire to offer this Encyclical Letter in testimony of Our gratitude. It tells of those living stones which rest upon the living cornerstone, which is Christ, and are built together into a holy temple, far surpassing any temple built by hands, into a habitation of God in the Spirit.
Source: Mystici Corporis Christi (Vatican.va)