Catena Fidei

Revelation 21:14 (WEB)
The wall of the city had twelve foundations, and on them twelve names of the twelve Apostles of the Lamb.

Catechism · 4

§117Article 3 · Sacred ScriptureRead at vatican.va
The spiritual sense. Thanks to the unity of God's plan, not only the text of Scripture but also the realities and events about which it speaks can be signs.

§765Paragraph 1 · The Church in God's PlanRead at vatican.va
“Representing the twelve tribes of Israel, they are the foundation stones of the new Jerusalem.” — Catechism footnote: Cf. Mt 19:28; Lk 22:30; Rev 21:12-14.

§857Paragraph 3 · The Church is One, Holy, Catholic, and ApostolicRead at vatican.va
“The Church is apostolic because she is founded on the apostles, in three ways: - she was and remains built on "the foundation of the Apostles,"” — Catechism footnote: Eph 2:20; Rev 21:14.
§865Paragraph 3 · The Church is One, Holy, Catholic, and ApostolicRead at vatican.va
“For "the wall of the city had twelve foundations, and on them the twelve names of the twelve apostles of the Lamb."” — Catechism footnote: Rev 21:14.

Cyprian of Carthage, Epistles Letter 68
“Peter speaks there, on whom the Church was to be built, teaching and showing in the name of the Church, that although a rebellious and arrogant multitude of those who will not hear and obey may depart, yet the…” — editor's note: [Not any of his successors, but Peter personally, is thus honoured on the strength of Eph. ii. 20. All the apostles were in this foundation also, Rev. xxi. 14;…
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Jerome, Letters Letter 108
“She looked upon the camp of Gilgal and the hill of the foreskins suggestive of the mystery of the second circumcision: and she gazed at the twelve stones brought thither out of the bed of Jordan to be symbols of those twelve foundations on which are written the names of the twelve apostles.” — editor's note: Rev. xxi. 14.
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Tertullian, The Five Books Against Marcion III.23Book III
“This both Ezekiel had knowledge of and the Apostle John beheld.” — editor's note: Rev. xxi. 10–23.
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