"If ye had known me, ye should have known my Father also. . . . he that hath seen me hath seen the Father" (John 14:7,9).
The human aspect of the Father/Son relationship was not one of initial generation; that is, a created being, but did involve subordination. Christ willingly placed Himself in a subordinate position to the Father. As a son is to be completely obedient to his earthly father, even so, the Lord Jesus "humbled Himself, and became obedient" (Philippians 2:8) to His heavenly Father while on Earth. As an earthly son shares the same nature, essence and substance as his father, in another sense he is lesser because he is under his father's authority and control. Father and son are equal in nature, but the son is secondary in position.
This is exactly what happened when Christ came in the flesh. He, being fully God, "I and my Father are one" (John 10:30), became fully man, obediently placing Himself under His Father's control. Thus He could say, "my Father is greater than I" (14:28). Greater for those three and a half years in position but not in essence.
Christ's secondary position is clearly seen in the following statements. "I do nothing of myself; but as my Father hath taught me, I speak these things. . . . I do always those things that please Him" (8:28-29). "I can of mine own self do nothing" (5:30). "The Son can do nothing of Himself, but what He seeth the Father do" (5:19). "Therefore doth my Father love me, because I lay down my life, that I might take it again. . . . I have power to lay it down, and I have power to take it again. This commandment have I received of my Father" (10:17-18).
Believers should rejoice that Christ was willing to humble Himself and become obedient unto death for us. NPS