An argument that Christians often use to show Jesus's divinity from the Bible is that he had the authority to forgive sins. However, according to the Gospel of John the disciples also had authority to forgive sins.
John 20:23
If you forgive anyone his sins, they are forgiven; if you do not forgive them, they are not forgiven.
So Christians have two alternatives.
Either they stop arguing that Jesus is divine because he had the authority to forgive sins.
Or they change their doctrine and also believe that the disciples are also divine.
Appendix
Sam Shamoun in his article http://www.answering-islam.org/Shamoun/q_apostles_forgive_sins.htm tried to show that Jesus' way of forgiving was different from that of the disciples.
However, Sam proved nothing.
He only showed that the reason why the disciples were able to forgive sins was because Jesus gave them the authority to. Sam says...
The Apostles couldn’t do all these things if Christ hadn’t given them this Divine right.
However, anyone could simply argue back and say that Jesus was only able to forgive sins because he was given the authority to as well (Matthew 28:18).
Sam Shamoun also tried to show that Jesus Christ is divine. Because according to the Old Testament (Genesis 2:7, Joel 2:27-29) God poured out his spirit on flesh just like how Jesus did (John 20:22 and Acts 2:30-33). However, that does not prove that Jesus is divine. God could have simply done it through the agency of Jesus Christ.
Notice what the verse says
Acts 2:30-33
30But he was a prophet and knew that God had promised him on oath that he would place one of his descendants on his throne. 31Seeing what was ahead, he spoke of the resurrection of the Christ,[a] that he was not abandoned to the grave, nor did his body see decay. 32God has raised this Jesus to life, and we are all witnesses of the fact. 33Exalted to the right hand of God, he has received from the Father the promised Holy Spirit and has poured out what you now see and hear.
The verse clearly shows that the Holy Spirit is originally being given from the Father. So the Father is giving the Holy Spirit through Jesus Christ.
Also notice another error that Shamoun makes. He says that only Christ alone could forgive sins.
These next examples confirm that this is how the Apostles forgave sins, not on the basis of their own authority like Jesus did, but in the name of Christ who alone forgives sins:
But I do not see this when I look at the teachings of Jesus.
Matthew 6:9-15
"This, then, is how you should pray:
" 'Our Father in heaven,
hallowed be your name,
10your kingdom come,
your will be done
on earth as it is in heaven.
11Give us today our daily bread.
12Forgive us our debts,
as we also have forgiven our debtors.
13And lead us not into temptation,
but deliver us from the evil one.[a]' 14For if you forgive men when they sin against you, your heavenly Father will also forgive you. 15But if you do not forgive men their sins, your Father will not forgive your sins.
We all know that Christ is different from the Father (even though they are one in essence according to Christian belief). This shows that the Father forgives and not only Jesus does. Secondly, why doesn't Jesus just simply state that we should ask him for forgiveness?
Sam has proved nothing. The disciples forgave sins because they had the authority to. Jesus forgave sins because he had the authority to as well. People may argue that only God could give the authority and since Jesus gave the authority then that means he is God. Well not necessarily because remember Jesus was GIVEN all authority by God and so it is possible that this authority which was GIVEN to him also included giving authority to other people.
Also read http://www.answering-christianity.com/sami_zaatri/rebuttaltosamshamoun5_1.htmsource : www.answering-christianty.com