The thief cometh not but for to steal
That is his first and principal view; to steal, is to invade, seize, and carry away another's property. Such teachers that come not in by the right door, or with a divine commission, seek to deceive, and carry away the sheep of Christ from him, though they are not able to do it; and to steal away their hearts from him, as Absalom stole the hearts of the people from their rightful lord and sovereign, David his father; and to subject them to themselves, that they might lord it over them, and make a property of them, as the Pharisees did, who, under a pretence of long prayers, devoured widows' houses.
And to kill and to destroy;
either the souls of men by their false doctrines, which eat as doth a cancer, and poison the minds of men, and slay the souls that should not die, subverting the faith of nominal professors, though they cannot destroy any of the true sheep of Christ; or the bodies of the saints, by their oppression, tyranny, and persecution, who are killed all the day long for the sake of Christ, and are accounted as sheep for the slaughter, by these men, they thinking that by so doing they do God good service.
I am come that they might have life;
that the sheep might have life, or the elect of God might have life, both spiritual and eternal; who, as the rest of mankind, are by nature dead in trespasses and sins, and liable in themselves to an eternal death: Christ came into this world in human nature, to give his flesh, his body, his whole human nature, soul and body, for the life of these persons, or that they might live spiritually here, and eternally hereafter; and so the Arabic version renders it, "that they might have eternal life"; Nonnus calls it, "a life to come"; which is in Christ, and the gift of God through him; and which he gives to all his sheep, and has a power to give to as many as the Father has given him:
and that they might have [it] more abundantly;
or, as the Syriac version reads, "something more abundant"; that is, than life; meaning not merely than the life of wicked men, whose blessings are curses to them; or than their own life, only in the present state of things; or than long life promised under the law to the observers of it; but even than the life Adam had in innocence, which was but a natural and moral, not a spiritual life, or that life which is hid with Christ in God; and also than that which angels live in heaven, which is the life of servants, and not of sons: or else the sense is, that Christ came that his people might have eternal life, with more abundant evidence of it than was under the former dispensation, and have stronger faith in it, and a more lively hope of it: or, as the words may be rendered, "and that they might have an abundance": besides life, might have an abundance of grace from Christ, all spiritual blessings in him now, and all fulness of joy, glory, and happiness hereafter.