The flip side of that is that not all sins are paid for, therefore Jesus does not die for all. With this post, I hope to demonstrate that Christ knew He died for a specific group of people and was explicit about who he was dying for.
I am the good shepherd. The good shepherd lays down his life for the sheep.12 He who is a hired hand and not a shepherd, who does not own the sheep, sees the wolf coming and leaves the sheep and flees, and the wolf snatches them and scatters them.13 He flees because he is a hired hand and cares nothing for the sheep.14 I am the good shepherd. I know my own and my own know me,15 just as the Father knows me and I know the Father; and I lay down my life for the sheep.16 And I have other sheep that are not of this fold. I must bring them also, and they will listen to my voice. So there will be one flock, one shepherd.17 For this reason the Father loves me, because I lay down my life that I may take it up again.18 No one takes it from me, but I lay it down of my own accord. I have authority to lay it down, and I have authority to take it up again. This charge I have received from my Father."
Which sheep is he laying down his life for? Jesus points out that he has a flock that contain his own sheep. (v.14) By extension, these are the sheep that Jesus is laying down his life for. Of course, we must now ask, "are all people Jesus' sheep?"
In response to this question, we point back to v.14 again
Well, we do know that Jesus knows everyone in a sense. But there is a specific meaning where Jesus does not know someone. Namely, that He does not love someone. (Matthew 7:21-23 is an example of this) Jesus also says that His sheep know Him, which certainly isn't true of many of the people of the world, as the Gospel of John testifies to so clearly (John 1:9-13).
v.14b)I know my own and my own know me
On top of that Jesus makes it very clear that not all people are His sheep in verse 16
16So we cannot understand Jesus saying "my sheep" in v. 14 to refer to all people as then his statement that there are other sheep not of this fold makes no sense. But maybe that just means that eventually he's going to be bringing all people into His fold. Setting aside what the question of "what does it mean that he knows his sheep in the same way that the Father knows the Son?" we can deal with that objection from the text (further in the passage).
And I have other sheep that are not of this fold. I must bring them also, and they will listen to my voice. So there will be one flock, one shepherd.
22At that time the Feast of Dedication took place at Jerusalem. It was winter, 23and Jesus was walking in the temple, in the colonnade of Solomon. 24So the Jews gathered around him and said to him, "How long will you keep us in suspense? If you are the Christ, tell us plainly." 25Jesus answered them,
"I told you, and you do not believe. The works that I do in my Father's name bear witness about me,26 but you do not believe because you are not part of my flock.27 My sheep hear my voice, and I know them, and they follow me.28 I give them eternal life, and they will never perish, and no one will snatch them out of my hand.29 My Father, who has given them to me,[a] is greater than all, and no one is able to snatch them out of the Father's hand.30 I and the Father are one."
26What does Jesus do for His sheep? He saves them. He gives them eternal life and they will never perish. Not "if they accept my offer they will never perish" but an automatic gift of God. No one will snatch them out of His hand (his sheep are already in His hand!). Those who are His sheep are saved. They will never perish and this is the promise of Christ. Hand in hand with Christ dying for them is Christ saving them.
but you do not believe because you are not part of my flock.27 My sheep hear my voice, and I know them, and they follow me.28 I give them eternal life, and they will never perish, and no one will snatch them out of my hand.29 My Father, who has given them to me,[a] is greater than all, and no one is able to snatch them out of the Father's hand.30 I and the Father are one."
Jesus is the good shepherd. He knows His sheep and lays down His life for His sheep. He never loses them because they are held by God's powerful hand. Soli Deo Gloria