1. Typically, there were large sheepfolds containing more than one flock. There would be a gate and a gatekeeper. I imagine the gatekeeper would be paid by all the shepherds who had their flock in the sheepfold. The gatekeeper would then only allow shepherds who had sheep in the sheepfold to enter. If a person came who was not a legitimate shepherd, they would have to sneak over the wall. They would be there only to steal from the shepherd, or kill and destroy his flock.
The real shepherd of a flock would be allowed in. He would call to his sheep and because they recognized his voice they would follow him out into he pasture to eat and roam. Knowing them each very well, He has given them each a name. He would walk before them, always talking so they knew where he was headed and could follow. The sheep which were not part of a particular shepherd's flock would stay in the large sheepfold and not follow, or most likely run from another shepherd because they wouldn't recognize his voice.
Once out in the pasture, there may be a smaller sheepfold as pictured above. The sheep would enjoy their day in the pasture under the watchful eye of the shepherd and then be led into a one flock sheepfold where the shepherd would sit in the opening, acting as a gate, allowing only his sheep to come and go.
Note that Jesus uses 3 versions of the shepherd and the sheep.
In the first 5 verses of John 10, Jesus described how the larger, multi-flock sheepfold worked. This would be much more familiar to the people in his time. We have to work a little harder to grasp the sheepfold idea.
The first version was to basically spell out the everyday use of sheep, sheepfold and shepherd. You will see my comments on that above as 1. The people listening to Jesus didn't understand what He meant by that, so Jesus explained using the smaller one flock sheepfold concept.
2. He declared that He is the gate (that thought is pictured very well in the above picture). He said He is the gate for the sheep. We can see that no robber or predator can get to His sheep because they would have to get past Him. The only possible way for anyone to get in to steal or kill would be to sneak over the wall. Acting as the gate, the true shepherd's sheep would have to come and go through him. The sheep could go out to pasture or back into the security and provision of the sheepfold only through the shepherd. So it is with Jesus. His true followers could only enter the protection and provision of God through Him or go out into the richness of the pasture under His watchful eye.
He said there were those that came before Him claiming to be the true shepherd. They claimed to have the best interests of the sheep in mind. Jesus was speaking of the Pharisees. They acted like they had the best spiritual interests of the people in mind but they really only cared for themselves. Those who were not the true shepherd, were the thieves and robbers Jesus spoke about.
As the true shepherd, Jesus cares about the safety, protection, and provision of His followers (sheep). He cares about their lives, well being, and their eternal destination. Those that entered through Jesus would be saved and be safe. He compared the purpose of a thief to His purpose. In verse 10, He told the people the purpose of the thief (the false shepherd, the Pharisees) was to care for himself. He was in it to become rich and live a good life, and as he saw it, secure a place in God for himself. The false shepherds were there to steal from Jesus' flock, to kill them and to destroy the flock. Jesus' purpose was to give the flock life and a life filled with blessing. The thief destroys the lives of the sheep but Jesus came to give them life.
3. Now the third version is this. We might say Jesus explained the difference between a good shepherd and a bad one. Jesus begins this part by saying, "I am the good shepherd." He then went on to compare the good shepherd with a hired hand. The good shepherd (Jesus) sacrifices His life for the sheep. The good shepherd knows His sheep and they know Him just as well as the Father knows Jesus and Jesus knows the Father. Because of this knowledge, care, and love they all have for each other Jesus sacrifices His life for the sheep. Jesus also has other sheep not in this particular sheephold. Jesus is referring to the Gentiles as the other sheep. Jesus has come to also bring them into the sheepfold with all the other sheep (Jews). They too will know His voice, hear Him, and follow Him into God's protection and provision. Once that happens, there will be only one flock (Jews and Gentiles) and only one true shepherd - Jesus.
On the other hand, one who is only a hired hand and not the true shepherd, will run away when he sees a wolf coming. He will abandon the sheep for his own well being because they are not his sheep. With no protection, the sheep will be attacked and scattered by the wolf.
Israel has experienced many false leaders. They have been ruled by kings, prophets, religious leaders, Pharisees, and such who really didn't care about the people and when trouble came, they would look out only for themselves. They would simply abandon the people. Jesus told them He was their true shepherd and He would be there to protect them, bring them into His family, provide for them, watch over them and even die for them.
The Father loved Jesus because He was willing to sacrifice His life. Once He sacrificed His life, He would then be able to be resurrected on behalf of the sheep. He was not forced to give His life but gave it voluntarily. He has the authority to lay down His life and pick it back up again. Jesus had the power to die for the people and then be resurrected for them. It was the Father's will and He did it without any reluctance. There was no one who could take Jesus' life from Him. Not the Pharisees, the Romans, nor any other power in the universe. His life could not be taken, it could only be given by Him.
When the people heard all of that, they were not in agreement. Some said He must be possessed by a demon and was out of His mind. Others said He didn't sound like a person who was demon possessed. In fact, how could a person possessed by a demon open the eyes of the man who had been blind from birth. As we read the account of Jesus' healing of the blind man, we read that God doesn't listen to an evil person making it impossible for a demon possessed person to heal anyone, especially a person born blind at birth.
Jesus then went on to Jeruselem. It was winter and the time of Hanukkah or the Feast of Lights. It was celebrated to remind them of their great rescue and delivery from their enemies. He was walking in the Temple and became surrounded by religious leaders. We know how their hatred for Jesus continued to grow. It seems like none of their other attempts to trap Him worked so they came at Him with a blunt all telling question. They simply said (vs. 24) NLT, "The people surrounded Him and asked, "How long are you going to keep us in suspense? If you are the Messiah, tell us plainly."
Jesus replied that he had already told them but they had not believed. He told them several times, to which they always asked for proof. If we think back, nearly every encounter about who Jesus was, ended with the leaders demanding proof. Apparently, Jesus wasn't going to bother telling them who He was again and then having to listen to their demands for proof. He went straight to the point by answering their demand for proof by telling them, "The proof is the work I do in my Father's name."
Even at that, Jesus told them the problem about their lack of faith is that they are not His sheep. Jesus told them that His sheep know Him, His voice, and follow Him. In that, He gives His sheep eternal life, they will never perish and no one could ever take them from Him. They cannot be taken from Him because the Father has given them to Him and no one is more powerful than the Father. No one can take them from the Father and the Father and Jesus are one.
The people again picked up stones to kill Jesus. Jesus asked them, "At my Father's direction I have done many good works. For which one are you going to stone me?" Jesus had not sinned but only been obedient to the Father's will. He had done only good things and there was no possible reason for them to stone Him. If they did stone Him, it could only be for a good thing He had done - because He had only done good things.
They answered back that they were not going to stone Him for any good work but for blasphemy. Jesus said He and the Father were one and to them that was blasphemy. Jesus did indeed claim that He was God by saying he and he Father were one. They saw Him as a mere man claiming to be God and therefore a blasphemer who should be stoned.
Jesus answered back reminding them of the writing in "your" Law. "The" Law usually refers to the first five books of the Old Testament. In this case what is meant by what Jesus said was the Old Testament not just the first five books. By saying, "your" law, Jesus was saying they thought of it as their own law as if they owned it themselves. In the Old Testament, it is written that God said to certain leaders, "I say you are gods." God was not referring to them in a likeness with Him or as any type of deity. He was saying they did what they wanted, judged as they saw fit and ruled any way they wanted. He was saying they ran things as if they were gods. It was a criticism not a compliment. He was using their thinking against them; if your law says some of you are gods and if the law cannot be broken or even thought of as wrong, then how could it be wrong to say that He was the Son of God?
Jesus went on to say "After all, the Father set me apart and sent me into the world. Don't believe me unless I carry out my Fathers work. But if I do His work, believe in the evidence of the miraculous works I have done, even if you don't believe me." The Jews refused to believe Jesus and His claims , Jesus shows them that the Father was giving them all miracles to prove Jesus was who He said He was. Jesus was telling them if they did not believe His words, believe the things done by Him as proof of the truth. If they looked at all He had done they would then "...know and understand that the Father is in me and I am in the Father." If they looked at all the miraculous things Jesus did, they would have to see Jesus was in the Father and the Father was in Him. No one other than that would be able to do the things Jesus did.
They again refused to believe and resorted to trying to arrest Him. Jesus left and went back to where John had first been baptizing. Many people followed Him. The people who followed were talking about how John did not do any miracles, "but everything he (John) said about this man has come true." Many who were there then believed in Jesus.