But new wine must be put into new bottles,.... Such as the disciples of Christ were, and sinners called to repentance are, who are renewed by the Spirit and grace of God: and these are filled with spiritual joy and comfort, as with new wine, arising from discoveries of the love of God, a view of interest in the blessings of the covenant, and an application of Gospel truths and promises. And both are preserved; both these renewed ones, who are preserved unto the kingdom and glory of Christ; and the grace that is put into them, which is a well of living water, springing up to everlasting life; as well as the Gospel, and its blessings.