Taken alone, these three verses could give us the impression that salvation is a free, downhill ride. However, II Peter 1:10 levels the playing field considerably in its sobering instruction: "Therefore, brethren, be even more diligent to make your calling and election sure, for if you do these things you will never stumble." If salvation is a free coast into the Kingdom, why does Peter admonish us to be diligent to make sure we do not fall? Paul adds that we have a responsibility to "work out [our] own salvation" (Philippians 2:12). These instructions do not contradict but complement and balance, making our responsibilities more specific and varied.
John W. Ritenbaugh
The Sovereignty of God and Human Responsibility: Part Eleven
God the Father, who raised Jesus from the dead, dwells in each member of His church through His Holy Spirit, and by it He will also give eternal life to them (Romans 8:11). Therefore, the life given to the sheep is the same Spirit that dwells in the Father, in the Shepherd, and in the sheep. Because the Shepherd gave His life for the sheep, sacrificing all, He is able to give abundant, eternal life to them by removing the obstacle of death, the penalty for sin, by the resurrection from the dead.
No one can steal His sheep from Him because they are, in effect, in the palm of His hand (I Peter 5:6; Revelation 1:17). Nothing could be safer or more secure. The Shepherd and His Father are one, and Their grip is tightly on Their church so that even "the gates of Hades shall not prevail against it" (Matthew 16:18).
Thus, with a large number of sheep, the true Shepherd may shelter them in many pens, but they are still all His sheep and all one flock. The flock does not create this unity, but because the nature of the sheep is in harmony with their Shepherd, and because their relationship to Him is intimate, they recognize and obey His voice: "My sheep hear My voice, and I know them, and they follow Me" (John 10:27).
Martin G. Collins
Parable of the Good Shepherd (Part Two)