James 5:13-14
13. Is any among you afflicted? let him pray. Is any merry? let him sing psalms. 
14. Is any sick among you? let him call for the elders of the church; and let them pray over him, anointing him with oil in the name of the Lord: 

Matthew 9:1-7
1.  And he entered into a ship, and passed over, and came into his own city. 
2.  Note And, behold, they brought to him a man sick of the palsy, lying on a bed: and Jesus seeing their faith said unto the sick of the palsy; Son, be of good cheer; thy sins be forgiven thee. 
3.  And, behold, certain of the scribes said within themselves, This man blasphemeth. 
4.  And Jesus knowing their thoughts said, Wherefore think ye evil in your hearts? 
5.  For whether is easier, to say, Thy sins be forgiven thee; or to say, Arise, and walk? 
6.  But that ye may know that the Son of man hath power on earth to forgive sins, (then saith he to the sick of the palsy,) Arise, take up thy bed, and go unto thine house. 
7.  And he arose, and departed to his house. 
Hermna's Notes.
Christ is using his ability to perform miracles as evidence that he is God, and therefore has the right to forgive sins.

He is saying, anyone can say "Your sins are forgiven," without any evidence that they have the authority to do so. Both sentences are easy to just say, but you need to look beyond the act of speaking and look at what Jesus is doing.

But only God can heal a paralytic. So by performing such a miracle, Christ is proving that he has the authority of God both to heal and to forgive sin. The pharisees questioned Jesus' authority to forgive sins, so he showed his authority by healing the paralyzed man.

You must take verses 5 and 6 together, as they're a single statement. Christ has just told the paralyzed man that his sins are forgiven, and the teachers around Him that saw it believed His statement of forgiveness was blasphemy as only God can forgive sins. They failed to recognize that Christ was God. So, He then makes a point of showing them that it's just as easy for Him to heal a body as it is to forgive sins. He then solidifies His position by healing the man, proving that He does have power over the physical, removing their doubt of his power over the spiritual.

Jesus has pronounced forgiveness of the man's sins. The Pharisees object, saying that "only God can forgive sins". The Pharisees would agree that forgiving sins is easier than having the man walk again, so Jesus makes him walk again as a clear demonstration that he has the power to do both. It has nothing to do with the sickness being caused by sin. 

Mark 2:1-12
1.  And again he entered into Capernaum after some days; and it was noised that he was in the house. 
2.  And straightway many were gathered together, insomuch that there was no room to receive them, no, not so much as about the door: and he preached the word unto them. 
3.  And they come unto him, bringing one sick of the palsy, which was borne of four. 
4.  And when they could not come nigh unto him for the press, they uncovered the roof where he was: and when they had broken it up, they let down the bed wherein the sick of the palsy lay. 
5.  When Jesus saw their faith, he said unto the sick of the palsy, Son, thy sins be forgiven thee. 
6.  But there were certain of the scribes sitting there, and reasoning in their hearts, 
7.  Why doth this man thus speak blasphemies? who can forgive sins but God only? 
8.  And immediately when Jesus perceived in his spirit that they so reasoned within themselves, he said unto them, Why reason ye these things in your hearts? 
9.  Whether is it easier to say to the sick of the palsy, Thy sins be forgiven thee; or to say, Arise, and take up thy bed, and walk? 
10.  But that ye may know that the Son of man hath power on earth to forgive sins, (he saith to the sick of the palsy,) 
11.  I say unto thee, Arise, and take up thy bed, and go thy way into thine house. 
12.  And immediately he arose, took up the bed, and went forth before them all; insomuch that they were all amazed, and glorified God, saying, We never saw it on this fashion.

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Did you know? - Jesus NEVER said 'No" to anyone who came to Him for healing.. Jesus NEVER said it was God's will they be sick.. Jesus NEVER said anyone was being perfected by their sickness.. so just who DID say that?? Read my latest book. The traditions of men, the lies of the devil and why Christians struggle with faith. 

Proverbs 4:20
20. My son, attend to my words; incline thine ear unto my sayings. 

Proverbs 5:1-2
1.  My son, attend unto my wisdom, and bow thine ear to my understanding: That thou mayest regard discretion, and that thy lips may keep knowledge. 

Psalms 103:2-3 
2.  Bless the LORD, O my soul, and forget not all his benefits:
3.  Who forgiveth all thine iniquities; who healeth all thy diseases;

John 6:63
It is the spirit that quickeneth; the flesh profiteth nothing: the words that I speak unto you, they are spirit, and they are life.