Heidelberg Catechism Question 54 asks “What do you believe concerning the ‘holy catholic church’ of Christ?”
That the Son of Goda from the beginning to the end of the world,b gathers, defends, and preservesc to himself by his Spirit and word,d out of the whole human race,e a church chosen to everlasting life,f agreeing in true faith;g and that I am and forever shall remain,h a living member thereof.i
Catholicity, the second attribute of this study, shows how the church embodies true believers out of the complete human race from the beginning to the end of time in a unity of communion to praise God. Catholicity is about all believers in all places at all times. To mark catholicity with an address would be an oxymoron (i.e. Rome). It is an apparent contradiction of terms to say the church universal in Missoula. No the church universal is just that, universal. A visible expression of the universal church could be in Rome, but I will leave that topic for another post at another time (see Belgic Confession art. 29).
Cyril of Jerusalem in his Catechetical Lectures explained how catholicity also embraces human experience. Catholicity along with unity, the attribute that expresses how all believers together are one body, implies a universal community with people from “every tribe, tongue, and nation.” This community embraces the experience of a mixed community, who unite in praise of him who “so loved the world.” Public worship comprises the visible church in a mixed community like Missoula who unite to worship. Private devotion misses out in this universal corporate experience, thus public worship is preferred over private devotion. Remember, I am not arguing against private devotion, you must, but I am arguing that public worship takes priority in the Christian life and catholicity helps prove this. In addition, public worship is a picture of the heavenly worship we will one day all give together as the completed catholic church. There will be no closets in heaven, so there should not be closets in public worship.
aEph. 5:26; John 10:11; Acts 20:28; Eph. 4:11–13.
bPs. 71:17, 18; Isa. 59:21; 1 Cor. 11:26.
c Matt. 16:18; John 10:28–30; Ps. 129:1–5.
dIsa. 59:21; Rom. 1:16; Rom. 10:14–17; Eph. 5:26.
e Gen. 26:4; Rev. 5:9.
f Rom. 8:29, 30; Eph. 1:10–13.
g Acts 2:46; Eph. 4:3–6.
h Ps. 23:6; 1 Cor. 1:8, 9; John 10:28; 1 John 2:19; 1 Pet. 1:5.
i 1 John 3:14, 19–21; 2 Cor. 13:5; Rom. 8:10.
 Cyril of Jerusalem, Catechetical Lectures, 7.139–40.