What does John 10:1 mean when it says the one who climbs up another way is a thief and a robber?
Jesus is the door to the sheepfold. The one who climbs up another way pictures people trying to gain heaven by a way other than the one He described. Such intruders are thieves and robbers and will be cast out; the image is spiritual, not merely about stealing a literal sheep or lamb.
Les explains that in John chapter 10 Jesus uses Himself as the example of the shepherd of the sheep, and He is not only the shepherd but also the door to the sheepfold. When Jesus says the one who does not enter by the door but climbs up some other way is a thief and a robber, most people only picture somebody trying to steal a sheep or a lamb. But Les says this is a spiritual thing. It means people who try to gain heaven by a way other than what Jesus has described will be cast out as thieves and robbers. By contrast, the one who enters in by the door is the shepherd; the porter opens to him, the sheep hear his voice, he calls his own sheep by name, and he leads them out.
Verily, verily, I say unto you, He that entereth not by the door into the sheepfold, but climbeth up some other way, the same is a thief and a robber.