I was wondering if it is appropriate to sing O Sacrum Convivium during Lent or if it would be permissible to sing on Holy Thursday? It’s a beautiful hymn but there are some Alleluia’s and I don’t think you’re supposed to sing Alleluia’s during Lent.
If it has Alleluias in it, it’s not permitted to be sung during Lent since we aren’t allowed to sing “Alleluia.” It wouldn’t be permitted for Holy Thursday either since we aren’t allowed to sing it then either. It would be permissible on the Easter Vigil or Easter Sunday or anytime beyond that. Not during Lent or Holy Thursday or Good Friday.
This hymn is deal for the feast of Corpus Christi, a major feast that was instituted precisely to allow us to celebrate with great joy the Blessed Sacrament, with the Lenten restrictions of the Triduum. This way the hymn can be sung with the A-word, which is forbidden during Lent.
Not all versions of it have the Alleluia…Just off-hand, I know that the setting of O Sacrum Convivium by Richard Farrant does not include an Alleluia at all. I vaguely recall hearing that it’s not suitable for Holy Thursday, but can’t remember why - it could have been precisely because of the settings which have the Alleluia…Given that it is a eucharistic text, I don’t know why it wouldn’t be suitable at the Mass of the Lord’s Supper. As Chatter said, it’s ideal for Corpus Christi - I think it’s from Second Vespers of the feast.
The same holds true for Let All Mortal Flesh Keep Silence; although, if you dispense with the last verse, then you have an ideal hymn for Holy Thursday.