Today, read John 10.
There have been so many religious leaders throughout human history and they have spawned so many different religions. Some of these are connected to Jesus in some way, denying some biblical doctrines about him while affirming others. How does someone know that they have found the truth?
A big answer to that question is given to us here in John 10. Jesus described to the religious leaders (v. 1--“you Pharisees”) many truths about himself and his followers. Using the metaphor of shepherds, sheep, and the pen those sheep are kept in, Jesus taught that the true sheep know the difference between him--the good shepherd (v. 14) and false leaders (vv. 1, 8, 10, 12-13). Because they are true sheep, they know Jesus, Good Shepherd (vv. 3, 14). Because they are true sheep, they enter through Jesus, the true gate (v. 9). All of this describes the spiritual life that God gives to those who genuinely come to Christ. Following Jesus is not a matter of rationally choosing him over other leaders and instead of other religions. It is the result of the new life that God gives by faith. That new life--we call it regeneration--causes us to recognize Jesus as the Way, the Truth, and the Life, the only way to the Father (to paraphrase 14:6).
Do you ever wonder why some people follow Jesus intensely for a time, then are diverted by the voice of another shepherd? It is because they are not really sheep. Do you ever wonder why some sincere people don’t receive Jesus as the one the Bible describes him to be? It is because they are not true sheep. Anyone you meet who tells you that they are spiritual, that they love God, and/or that they like Jesus but don’t think he was really God is telling you that they are not part of God’s flock (vv. 25-26).
One of the benefits of being part of God’s flock is eternal security, which is taught here in verses 27-30. Verse 28b says, “they shall never perish; no one will snatch them out of my hand.” The reason is given in verse 29, “My Father, who has given them to me, is greater than all; no one can snatch them out of my Father’s hand.” There is no need to worry about losing your salvation. Your salvation is not up to you because salvation is a gift given by God that makes you a sheep. It is not dependent on you to remain saved because Jesus and the Father are holding on to you. So, take joy in the gift of eternal life and follow the voice of the shepherd. Continuing to follow him--the doctrine we call preserving in the faith--is evidence of your genuine nature as one of his sheep. Like literal sheep, you may stray at times, but when the shepherd calls you in repentance, you will listen and follow him. This is how you can know that you have eternal life. Let it give you confidence and joy as you serve him today.