The General Instruction of the Roman Missal, 2010 translation, has: “299. The altar should be built separate from the wall, in such a way that it is possible to walk around it easily and that Mass can be celebrated at it facing the people, which is desirable wherever possible.” And: “303. In building new churches, it is preferable for a single altar to be erected, one that in the gathering of the faithful will signify the one Christ and the one Eucharist of the Church.
In already existing churches, however, when the old altar is so positioned that it makes the people’s participation difficult but cannot be moved without damage to artistic value, another fixed altar, skilfully made and properly dedicated, should be erected and the sacred rites celebrated on it alone.”
Is it acceptable in 2025 to celebrate Mass with the people, on an altar against a wall, using this Roman Missal?
Notitiae 2000, page 171, has an Italian letter Prot. No. 2036/00/L at https://notitiae.ipsissima-verba.org/pdf/communicationes-2000-171-173.pdf dated 25 September 2000. It includes “Un altare posticcio può non essere sempre una soluzione dignitosa.” A translation: “Adding another altar may not always be a worthy solution.” (From a translation at https://adoremus.org/2007/12/letter-on-the-position-of-the-priest-during-the-eucharistic-liturgy/ ). But it seems to contradict GIRM 303, to be a lower level of authority, and not be as recent as the GIRM (the Latin having had further revisions in 2002).
The GIRM 277 b has “if the altar is not freestanding, the Priest incenses it while walking first to the right hand side, then to the left.” A new altar takes time to design, make and install. Should this be taken as instructions for until the new altar is installed, or that it is acceptable to continue celebrations on altars against walls, that makes the people’s participation difficult?
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A: I have several blogposts on this theme; for example, https://paulturner.org/ad-orientem/ .
The way I read these rubrics, altars are to be constructed in such a way that the priest faces the people for the Liturgy of the Eucharist. Where the people have gathered in an unrenovated preconciliar church or chapel, the rubrics tell the priest what to do. Under those rare circumstances, it is acceptable in 2025. In my view, retroverting a space by eliminating an installed freestanding altar or creating a new church without one is indefensible.