If you look it up, repentance is never mentioned in the gospel of John. If the people who teach "repent of your sins for salvation" were right and you indeed had to repent before you could be saved, then shouldn't it be there? If you think about the fact that the book of John is written for the purpose of getting lost people saved, you would expect that it would be filled with repentance. In fact you would expect that repentance was talked about the most specifically in the book of John. And yet it's not mentioned even once.
"And many other signs truly did Jesus in the presence of his disciples, which are not written in this book But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name." - John 20:30-31
John 20:30-31 proves that you can have life through the name of Christ without ever even knowing about the concept of repentance. It also proves that you can preach the gospel to the lost without preaching about repentance. If it was wrong to remove repentance from the gospel (as many people teach), then the gospel of John would be "wrong" because it also removed repentance from the gospel. But of course there's nothing wrong with any book of the Bible. It's all inspired by God and it's all perfect.
"And many other signs truly did Jesus in the presence of his disciples, which are not written in this book But these are written, that ye might believe that Jesus is the Christ, the Son of God; and that believing ye might have life through his name." - John 20:30-31
John 20:30-31 proves that you can have life through the name of Christ without ever even knowing about the concept of repentance. It also proves that you can preach the gospel to the lost without preaching about repentance. If it was wrong to remove repentance from the gospel (as many people teach), then the gospel of John would be "wrong" because it also removed repentance from the gospel. But of course there's nothing wrong with any book of the Bible. It's all inspired by God and it's all perfect.