John Calvin on Jude 1:19

19. These be they who separate themselves. Some Greek copies have the participle by itself, other copies add ἑαυτοὺς, “themselves;” but the meaning is nearly the same. He means that they separated from the Church, because they would not bear the yoke of discipline, as they who indulge the flesh dislike spiritual life. This is the common interpretation, and yet it seems inconsistent with what is previously said of these men, that they crept in stealthily, and “feasted” with the members of the Church. The ἑαυτοὺς, though retained by Griesbach, is excluded by Wetstein and others, being absent from most of the MSS. The verb ἀποδιορίζω, means to separate by a boundary two portions from one another, and hence metaphorically to separate or cause divisions: “These be they who cause divisions.” They were doing the same thing as those mentioned by Paul in Romans 16:17. They were producing discords in the Church, and not separations from it; and by continuing in it, they became “spots and stains” to its members. — Ed The word sensual, or animal, stands opposed to spiritual, or to the renovation of grace; and hence it means the vicious or corrupt, such as men are when not regenerated. For in that degenerated nature which we derive from Adam, there is nothing but what is gross and earthly; so that no part of us aspires to God, until we are renewed by his Spirit.

Jude 20-25

20. But ye, beloved, building up yourselves on your most holy faith, praying in the Holy Ghost,

20. Vos autem dilecti, sanctissimæ vestræ fidei vosmet superstruentes, in Spiritu Sancti precantes,

21. Keep yourselves in the love of God, looking for the mercy of our Lord Jesus Christ unto eternal life.

21. Vosmet in charitate servate, expectantes misericordiam Domini nostri Jesu Christi in vitam eternam.

22. And of some have compassion, making a difference.

22. Et hos quidem miseramini, dijudicantes;

23. And others save with fear, pulling them out of the fire; hating even the garment spotted by the flesh.

23. Illos verò per timorem servate, ex incendio rapientes, odio prosquentes etiam maculatam a’ carne tunicam.

24. Now unto him that is able to keep you from falling, and to present you faultless before the presence of his glory with exceeding joy,

24. Ei autem qui servare potest vos (vel, eos) à peccato immunes, et statuere in conspectu gloriae suae reprehensibiles cum exultatione,

25. To the only wise God our Saviour, be glory and majesty, dominion and power, both now and ever. Amen.

25. Soli sapienti Deo, Servatori nostro, gloria et magnificentia et perium et potestas, nunc, et in omnia secula. Amen.