Sin unforgivable

Apparently there are 2 (two) sin unforgivable, that is blasphemy against the Holy Spirit and not forgive the sins of others

1. Blaspheming the Holy Spirit

Luke 12:10 And whosoever shall speak a word against the Son of man, it shall be forgiven him: but unto him that blasphemeth against the Holy Ghost it shall not be forgiven. 

Mat 12:31 Wherefore I say unto you, All manner of sin and blasphemy shall be forgiven unto men: but the blasphemy against the Holy Ghost shall not be forgiven unto men.

Mat 12:32And whosoever speaketh a word against the Son of man, it shall be forgiven him: but whosoever speaketh against the Holy Ghost, it shall not be forgiven him, neither in this world, neither in the world to come.
Mark 3:29 But he that shall blaspheme against the Holy Ghost hath never forgiveness, but is in danger of eternal damnation.
Eph 4:30 And grieve not the holy Spirit of God, whereby ye are sealed unto the day of redemption.
5:19 Quench not the Spirit.
1 Corinthians 12:3 Wherefore I give you to understand, that no man speaking by the Spirit of God calleth Jesus accursed: and that no man can say that Jesus is the Lord, but by the Holy Ghost. 

Heb 6:4 For it is impossible for those who were once enlightened, and have tasted of the heavenly gift, and were made partakers of the Holy Ghost,
Heb 6:5 And have tasted the good word of God, and the powers of the world to come,
Hebrews 6:6 If they shall fall away, to renew them again unto repentance; seeing they crucify to themselves the Son of God afresh, and put him to an open shame.

2. Not forgive
Mat 6:14 For if ye forgive men their trespasses, your heavenly Father will also forgive you:
Mat 6:15 But if ye forgive not men their trespasses, neither will your Father forgive your trespasses.
Mark 11:25 And when ye stand praying, forgive, if ye have ought against any: that your Father also which is in heaven may forgive you your trespasses.
Mark 11:26 But if ye do not forgive, neither will your Father which is in heaven forgive your trespasses. 

Illustration - Matthew

18:23 Therefore is the kingdom of heaven likened unto a certain king, which would take account of his servants. 

18:24 And when he had begun to reckon, one was brought unto him, which owed him ten thousand talents. 

18:25 But forasmuch as he had not to pay, his lord commanded him to be sold, and his wife, and children, and all that he had, and payment to be made. 

18:26 The servant therefore fell down, and worshipped him, saying, Lord, have patience with me, and I will pay thee all. 

18:27 Then the lord of that servant was moved with compassion, and loosed him, and forgave him the debt. 

18:28 But the same servant went out, and found one of his fellowservants, which owed him an hundred pence: and he laid hands on him, and took him by the throat, saying, Pay me that thou owest. 

18:29 And his fellowservant fell down at his feet, and besought him, saying, Have patience with me, and I will pay thee all. 

18:30 And he would not: but went and cast him into prison, till he should pay the debt. 

18:31 So when his fellowservants saw what was done, they were very sorry, and came and told unto their lord all that was done. 

18:32 Then his lord, after that he had called him, said unto him, O thou wicked servant, I forgave thee all that debt, because thou desiredst me: 

18:33 Shouldest not thou also have had compassion on thy fellowservant, even as I had pity on thee? 

18:34 And his lord was wroth, and delivered him to the tormentors, till he should pay all that was due unto him. 

18:35 So likewise shall my heavenly Father do also unto you, if ye from your hearts forgive not every one his brother their trespasses.