Ekklesia, the Greek word typically translated church, occurs 115 times in the New Testament. Here are the four occurrences, which clearly refer to individual congregations:
Rom 16:5 Greet also the church in their house. Greet my beloved Epaenetus, who was the first convert to Christ in Asia.
1 Cor 16:19 The churches of Asia send you greetings. Aquila and Prisca, together with the church in their house, send you hearty greetings in the Lord.
Col 4:15 Give my greetings to the brothers at Laodicea, and to Nympha and the church in her house.
Philemon 1:2 and Apphia our sister and Archippus our fellow soldier, and the church in your house.
You could expand this list a bit to include verses about church assemblies, for example, Paul’s instructions on prophecy during gatherings in 1 Corinthians 14 (though that’s more applicable to a modern small group). When “church” is mentioned in the New Testament, the author is almost always referring to all believers everywhere or believers in a geographic area.
In the Western church, we have a tendency to focus too much on the church we attend. We look at Christians who attend other congregations differently. We think of growing our congregation instead of growing the believers in it (they aren’t mutually exclusive, of course). Can you imagine Paul instructing Prisca to lay down her life for the church in her house? The people, yes, but the place and the organizational structure? I can’t imagine that. As you can see, the verses that mention individual congregations give them no theological weight as an entity in themselves.
Local assemblies, and the structures that go with them, are absolutely necessary. They are where believers gather to worship together: to sing to God, to hear his Word, and to receive the sacraments. Hopefully, they are also where church discipline, pastoral care, and spiritual gifts are exercised. But they are a small part of the larger picture; after all, there are several hundred thousand churches in the US alone.
Considering praying for the Pope as a regular practice, or attend a prayer meeting at another church in your town, or connect with a believer who goes to a different church.
John 17:22-23 The glory that you have given me I have given to them, that they may be one even as we are one, I in them and you in me, that they may become perfectly one, so that the world may know that you sent me and loved them even as you loved me.