because you have been built on the foundation of the apostles and prophets, with Christ Jesus himself as the cornerstone. In him the whole building, being joined together, grows into a holy temple in the Lord, — Eph 2:20-21 NET
Christ is the Head of every member individually, as he is the Head of the whole body collectively. Growth of the body, from babyhood to manhood, is the growth of individual members in the body. If, then, I am a member of the mystical body of Christ Jesus, I shall grow. My growth may be so slow and gradual as to be scarcely perceptible; but it will be growth still. If I have union with Christ, I shall be supplied, at least in some measure, out of his fullness. He is my life, and he has promised, because he lives, I shall live also; and if I live by him, I shall live upon and unto him. Paul could say, “The life which I live in the flesh I live by the faith of the Son of God;” and also, “And that he died for all, that they which live should not henceforth live unto themselves, but unto him which died for them, and rose again” (2 Cor. 5:15).
By a sound gospel ministry our souls are fed. Christ is set before us in all the glories of his divine Person—in his Deity and Sonship, and in all the graces of his suffering humanity. His covenant characters and gracious relationships, his blood and righteousness, his death and resurrection, his ascension and glorification at the right hand of the Father, his present mediation and intercession, his sympathy as a once suffering but now exalted high Priest, and his ability to save to the uttermost all that come to God by him, are brought before us as the food of our faith; and as we taste that he is gracious, and feed upon him as the bread of life, there is a growth into him.