20. Translate as Greek, "Built up upon," &c. (participle; having been built up upon; omit, therefore, "and are"). Compare 1Co 3:11, 12. The same image in Eph 3:18, recurs in his address to the Ephesian elders (Ac 20:32), and in his Epistle to Timothy at Ephesus (1Ti 3:15; 2Ti 2:19), naturally suggested by the splendid architecture of Diana's temple; the glory of the Christiantemple is eternal and real, not mere idolatrous gaud. The image of a building is appropriate also to the Jew-Christians; as the temple at Jerusalem was the stronghold of Judaism; as Diana's temple, of paganism.
      foundation of the apostles, &c.--that is, upon their ministry and living example (compare Mt 16:18). Christ Himself, the only true Foundation, was the grand subject of their ministry, and spring of their life. As one with Him and His fellow workers, they, too, in a secondary sense, are called "foundations" (Re 21:14). The "prophets" are joined with them closely; for the expression is here not "foundations of the apostles and the prophets," but "foundations of the apostles and prophets." For the doctrine of both was essentially one (1Pe 1:10, 11; Re 19:10). The apostles take the precedency (Lu 10:24). Thus he appropriately shows regard to the claims of the Jews and Gentiles: "the prophets" representing the old Jewish dispensation, "the apostles" the new. The "prophets" of the new also are included. BENGEL and ALFORD refer the meaning solely to these (Eph 3:5; 4:11). These passages imply, I think, that the New Testament prophets are not excluded; but the apostle's plain reference to Ps 118:22, "the head stone of the corner," proves that the Old Testament prophets are a prominent thought. David is called a "prophet" in Ac 2:30. Compare also Isa 28:16; another prophet present to the mind of Paul, which prophecy leans on the earlier one of Jacob (Ge 49:24). The sense of the context, too, suits this: Ye were once aliens from the commonwealth of Israel (in the time of her Old Testament prophets), but now ye are members of the true Israel, built upon the foundation of her New Testament apostles and Old Testament prophets. Paul continually identifies his teaching with that of Israel's old prophets (Ac 26:22; 28:23). The costly foundation-stones of the temple (1Ki 5:17) typified the same truth (compare Jer 51:26). The same stone is at once the corner-stone and the foundation-stone on which the whole building rests. Paul supposes a stone or rock so large and so fashioned as to be both at once; supporting the whole as the foundation, and in part rising up at the extremities, so as to admit of the side walls meeting in it, and being united in it as the corner-stone [ZANCHIUS]. As the corner-stone, it is conspicuous, as was Christ (1Pe 2:6), and coming in men's way may be stumbled over, as the Jews did at Christ (Mt 21:42; 1Pe 2:7).

JFB.