Whether general or local, the church consisted of those who were "sanctified in Christ Jesus" (I Cor. i. 2) or "called to be saints" (Rom. i.7), with a possible allusion to the etymological connection between kletoi and ekkesia. Paul's conception was characterized by a deep sense of the unity constituted by the possession of "one Lord, on faith, one baptism" (Eph. iv. 5); and elsewhere the entrance into this united fellowship, both with Christ and with each other, was attached to baptism (Gal.iii. 27; I Cor. xii. 13).
–New Schaff-Herzog Encyclopedia of Religious Knowledge [Dictionary edition]