A.T. Robertson Commentary John 10:28

"and I give unto them eternal life; and they shall never perish, and no one shall snatch them out of my hand." — John 10:28 (ASV)

And I give unto them eternal life (καγω διδωμ αυτοις ζωην αιωνιον). This is the gift of Jesus now to his sheep as stated in 6:27,40 (cf. 1 John 2:25; 5:11).

And they shall never perish (κα ου μη απολωντα). Emphatic double negative with second aorist middle (intransitive) subjunctive of απολλυμ, to destroy. The sheep may feel secure (3:16; 6:39; 17:12; 18:9).

And no one shall snatch them out of my hand (κα ουχ αρπασε τις αυτα εκ της χειρος μου). Jesus had promised this security in Galilee (6:37,39). No wolf, no thief, no bandit, no hireling, no demon, not even the devil can pluck the sheep out of my hand. Cf. Colossians 3:3 (Your life is hid together with Christ in God).