John 10:29-30: The Shepherd's Repeated Promise
John 10:29-30: My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father’s hand. I and the Father are one.” 
After describing His sheep,  Jesus reiterates salvation’s permanence in believers.  Christ’s teaching on the saints’ perseverance  is reinforced by His and the Father’s graciously choosing the sheep.  Because God has predestined His people to saving faith, not on the basis of their free will or works,  He will complete the work.  Yes, Christians are responsible for their actions,  but their efforts do not earn salvation or qualify them for heaven. 
Jesus makes this promise because He is one with God the Father. Only God could promise John 10:29,  and God has in Christ. No sin, sinner, circumstance, etc. can “snatch” us when we embrace Jesus Christ as our exclusive means of salvation.  Even if your worst nightmare comes true, and comes with all Hell’s power, it could not shake the Son’s and Father’s double clenched fists around you.  These hands greet the elect into heaven, and all who repent of their sins.
 The Holy Bible: English Standard Version. (Wheaton, IL: Standard Bible Society, 2016). Logos Bible Software.
 Please see John 10:27-28 and corresponding blog titled “The Shepherd’s Sheep.”
 Andreas J. Kostenberger. John: Baker Exegetical Commentary on the New Testament. (Grand Rapids, MI: Baker Publishing Group, 2004).
 For a thorough definition please see The Westminster Confession of Faith, chapter XVII. For now, it will suffice to say “perseverance of the saints” means God’s true elect will be eternally saved despite life’s struggles.
 James Montgomery Boice. The Gospel of John, Volume 3: Those Who Received Him John 9-12. (Grand Rapids, MI: Baker Book House Company, 1999), 780.
 Calvin, John. Commentary on the Holy Gospel of Jesus Christ According to John. Trans. William Pringle. (Grand Rapids, MI: Baker Book House, 1981), 416. See also Ephesians 1:3-10, 2:1-10.
 Philippians 1:6; Psalm 57:2, 138:8; 1 Corinthians 1:8; 2 Corinthians 9:8; Galatians 3:3; 1 Thessalonians 5:24.
 John 6:29; 2 Corinthians 7:1; Galatians 3:10; Philippians 1:10, 2:16; 1 Thessalonians 1:3, etc.
 Judges 7:2; Romans 3:27-28, 4:1-10, 9:11, 11:6; Ephesians 2:9; 1 Corinthians 1:28-31; 2 Timothy 1:9; Titus 3:4-7.
 John Calvin, Institutes of the Christian Religion. Translated by Henry Beveridge. (Peabody, Mass: Hendrickson Publishers, Inc., 2008), II.viii.26, page 248.
 Romans 8:31-39, and Calvin, Institutes, III.xxii.11, page 623.
 Boice, The Gospel of John, 783-784 and Calvin, Institutes, III.xxii.11, page 623.