Article XIX, free-styled: The esse of the Church Militant (Ecclesia Christi visibilis) is the gathering of the faithful (coetus fidelium), whose ratio is twofold, being the topos where (1) the verbum Dei is proclaimed (praedicatur) and (2) the sacramenta are administered (administrantur) correctly, e.g., done with "all those things that of necessity are requisite, according to Christ's ordinance."
The church is performative: it is the coming together of those who believe, in which there is the proclaiming of God's word and the giving of the gifts of God. It is, of necessity, relational. And it thus engenders further performances, which (should) spiral forth: i.e., works of love and charity.
It is not a mere building, which, most unfortunately, may be shamelessly profaned:
In 2007 the Cathedral of St John the Divine in New York let its premises to the singer Elton John to celebrate his 60th birthday. John, who months before gave voice to his disdain for Christianity, noting he would “ban religion completely … Organized religion doesn’t seem to work. It turns people into hateful lemmings, and it’s not really compassionate,” turned the Diocese of New York’s cathedral into a ballroom.
The New York Post reported that for John’s party “the altar was set up as a stage for the performers, which included the trendy rock group Scissor Sisters, Sting and Paul McCartney.”