Ephesians 2:20 → Isaiah 28:16

Paul's image of the church "built on the foundation of the apostles and prophets, with Christ Jesus Himself as the cornerstone" (akrogōniaios) draws on the OT stone-cluster in which Isaiah 28:16 is the positive-pole anchor — the precious cornerstone and sure foundation that Yahweh promised to lay in Zion. Where Isaiah names the stone's identity (tested, precious, sure), Paul names its eschatological fulfillment: the stone Yahweh laid is Christ, and the structure raised upon it is the new-covenant people, Jew and Gentile together (Eph 2:11-19). The allusion is part of a fused stone-and-temple complex (Isa 28:16 + Ps 118:22) that the NT routinely bundles, and Paul immediately develops the temple-ecclesiology in vv. 21-22 ("a holy temple in the Lord... a dwelling place for God in His Spirit"). This is Promise-Fulfillment escalated by the Temple longitudinal theme: the foundation Yahweh promised is now the historical Christ on whom the church-temple actually rises. The telos is not a lesson in church order but the security and glory of being built into God's own dwelling on a foundation that cannot fail — the one who is joined to this cornerstone "will never be put to shame" (Isa 28:16 LXX), which makes Christ the cornerstone desirable, not merely structural.