John Calvin Commentary Colossians 2:19

"and not holding fast the Head, from whom all the body, being supplied and knit together through the joints and bands, increasing with the increase of God." — Colossians 2:19 (ASV)

Not holding the Head. With this one expression, he condemns whatever does not relate to Christ. He also confirms his statement on the basis that all things flow from him and depend upon him. Therefore, if anyone calls us to anything other than Christ, even if in other respects he seemed to encompass heaven and earth, he is empty and full of wind: let us, therefore, without concern, bid him farewell.

Observe, however, about whom he is speaking: namely, those who did not openly reject or deny Christ but, not accurately understanding his office and power, sought out other aids and means of salvation (as they commonly say) and so were not firmly rooted in him.

From whom the whole body by joints. He simply means this: the Church cannot stand unless all things are supplied to her by Christ, the Head. Accordingly, her entire safety consists in him. The body, it is true, has its nerves, its joints, and ligaments, but all these things derive their vigor solely from the Head, so that the entire way they are held together comes from that source.

What, then, must be done? The constitution of the body will be in a right state if the Head, which supplies the individual members with everything that they have, is simply allowed, without any hindrance, to have the preeminence. Paul speaks of this as the increase of God, by which he means that not every increase is approved by God, but only that which relates to the Head.

For we see that the kingdom of the Pope is not merely tall and large, but swells out into a monstrous size. However, since we do not see there what Paul here requires in the Church, what shall we say, but that it is a humpbacked body, and a confused mass that will fall to pieces by itself?