Matthew 9:5 NIV

5 Which is easier: to say, ‘Your sins are forgiven,’ or to say, ‘Get up and walk’?

Was Christ contrasting the two or he was referring to something else?

It is easier to say 'Thy sins be forgiven thee'.

The audience will not see anything happen. Anyone can say to anyone else, 'Thy sins be forgiven' and nobody will be any the wiser - until the Day of Judgement when it will be demonstrated (and that for all eternity) whether or not Almighty God is in agreement with the pronouncement.

So for Jesus to say 'Thy sins be forgiven thee' to the man proved nothing to any observers. The man would know, within himself, great relief. But outwardly, it would not demonstrate anything.

But a charlatan could do exactly the same. An impostor can mimic the words.

So Jesus admits that it is easier (by asking the question). But if he were a charlatan and had just uttered a fallacious blessing - would God hear ? Would God then enact a miracle at Jesus' word and would God support an impostor's request 'Rise up and walk' ?

Indeed not.

So saying, Jesus does exactly that. 'Rise up and walk !'

. . . Proving that he has power on earth to forgive sins, by demonstrating that God has supported his instruction to the man to walk and God has - miraculously - given the ability to the man.

Thus, the walking man shows that God heard Jesus' forgiveness and supports it.

He was prioritizing them two different ways: ability & importance

The "more important" is "easier"; the "lesser important" is "more difficult". Here is what I mean and why...

*Note, it is a rhetorical question: "which is easier for a fraud teacher to get away with saying?"

"easier" (able to prove)

Firstly, the direct answer to "easier" is "forgiving sin" because there is no proof, even though sin should have been more important to the Pharisees he was addressing. He healed the man, proving that he is not a fake, because claiming to have power to heal is not "easy" to get away with.

"priority" (the more important)

Secondly, he had already placed the greater priority on sin by forgiving the sin of the man who had come so far to get to him (v2). (Claiming he could forgive sin angered the Pharisees in the first place.)

one message, two applications

So, in these two ways, he proves that he has the authority to heal (the important, but secondary matter of physical health) to prove that he is not a fake and actually has authority over the greater and primary matter of forgiving sin.

The logic of the sentence goes that if man can do something more difficult, he surely would be able to do something easier. For instance, if one can rise a big stone, for sure the same one can rise also a smaller stone. Thus, here, according to this logic Jesus tells them that since to say to a cripple "get up and walk" with an effect that he would indeed get up and walk is more difficult than to say "your sins are forgiven" with an effect that the sins are really forgiven, then the truth and fact of the walking - more difficult - would have given them the trust in the forgiveness - easier.

But this is not of course Jesus' logic, but logic of those people, who think that bodily maladies and infirmities are graver and more troublesome than the maladies of soul, for what is sin but a malady of soul?! Thus, Jesus utilises their fallacious logic based on their fallacious value-system and gives proof that He really has forgiven the sin, that is to say, healed the inner, invisible malady of soul. But by this He also showed them that He has a divine authority, for as He heals the bodily malady not by praying to God, but by self-sovereign authority ("get up and walk!"), so does He heal his invisible malady, that is to say, forgives his sins, no through a prayer but by a self-sovereign authority, as God. Moreover, by healing the invisible malady, when the man did not ask about it, but only about the physical malady, Jesus, first, again, reprimanded this man that he also had the same value system as the others around him, and second, He showed to him that He knew his heart, which feature, that of "heart-knower" (Acts 1:24) is not a feature of any highest creature, like archangel or highest of prophets, but of God only.
Thus, we have a triple healing here:

1) healing of a physical malady

2) healing of a malady of soul, a.k.a. forgiving sins

3) healing of a wrongheaded value system of both the paralytic man and others around him who thought that physical malady is more important and more care-deserving than a malady of soul, which is sin.

Matthew 9:1-8 (DRB)

And entering into a boat, he passed over the water and came into his own city. 2 And behold they brought to him one sick of the palsy lying in a bed. And Jesus, seeing their faith, said to the man sick of the palsy: Be of good heart, son, thy sins are forgiven thee. 3 And behold some of the scribes said within themselves: He blasphemeth. 4 And Jesus seeing their thoughts, said: Why do you think evil in your hearts? 5 [Which] is easier, to say, Thy sins are forgiven thee: or to say, Arise, and walk? 6 But that you may know that the Son of man hath power on earth to forgive sins, (then said he to the man sick of palsy,) Arise, take up thy bed, and go into thy house. 7 And he arose, and went into his house. 8 And the multitude seeing it, feared, and glorified God that gave such power to men.

It appears that Jesus began to speak to the paralytic half way through what He was saying to the scribes ('But that you may know that the son of man has authority on earth to forgive sins: watch this for yourselves...'). I also maintain that the son of man here refers to 'mere mortals; men' and not the Son of Man of Daniel (i.e. Jesus) because of verse 7 ("who gave such power to men").¹ On the other hand, it could also refer to Jesus as one in the class "sons of men," in which case God still granted the power to forgive sins to men.² Or, "he then said" could refer to that He ("the Son of Man") had added after "thy sins are forgiven," "Arise and walk," but Matthew simply doesn't mention it the first time.³

"Which is easier to say" is a terse way of saying or explaining, "one cannot get away with saying, 'Arise and walk,' without being found a liar if they are a con; but you can say, 'Your sins are forgiven,' and it's unfalsifiable—easy to get away with—therefore, watch and see that I say it in truth, when God works a miracle before your very eyes, testifying to Me—when I do what is impossible for man, not only the more difficult."

Or, "it's easier for Me to simply say, 'You are forgiven,' and add nothing,' but when I add, 'Arise and walk,' I need to work a tangible miracle."

^{1 Matthew may be writing in retrospect of what is recorded in John 20:23. The use of the plural and not the singular is puzzling otherwise, unless "... to men" refers to the breaking of the barrier between God and men, and not that God actually gave this power to more than one man (if Jesus had been the only one to do this or have this power, would they not have said, "Who gave such power to a [mere] man?").}

^{2 Jesus is, after all, a real man. 1 Timothy 2:5.}

^{3 Cf. John 5:8.}