Let's begin with the consideration and review of two passages...
11 When the Pharisees saw it, they said to his disciples, “Why does your teacher eat with tax collectors and sinners?”
12 When Jesus heard it, he said to them, “Those who are healthy have no need for a physician, but those who are sick do.
13 But you go and learn what this means: ‘I desire mercy, and not sacrifice,’for I came not to call the righteous, but sinners to repentance.”*
14 Then John’s disciples came to him, saying, “Why do we and the Pharisees fast often, but your disciples don’t fast?”
15 Jesus said to them, “Can the friends of the bridegroom mourn as long as the bridegroom is with them? But the days will come when the bridegroom will be taken away from them, and then they will fast.
16 No one puts a piece of un-shrunk cloth on an old garment; for the patch would tear away from the garment, and a worse hole is made. 17 Neither do people put new wine into old wine skins, or else the skins would burst, and the wine be spilled, and the skins ruined. No, they put new wine into fresh wine skins, and both are preserved.”
18 John’s disciples and the Pharisees were fasting, and they came and asked him, “Why do John’s disciples and the disciples of the Pharisees fast, but your disciples don’t fast?”
19 Jesus said to them, “Can the groomsmen fast while the bridegroom is with them? As long as they have the bridegroom with them, they can’t fast. 20 But the days will come when the bridegroom will be taken away from them, and then they will fast in that day. 21 No one sews a piece of un-shrunk cloth on an old garment, or else the patch shrinks and the new tears away from the old, and a worse hole is made. 22 No one puts new wine into old wineskins; or else the new wine will burst the skins, and the wine pours out, and the skins will be destroyed; but they put new wine into fresh wineskins.”
In years past, I had just accepted that these passages were suggesting that a change was taking place, that there was to be a new economy, new model, a new law and and new covenant that was being instituted by the Messiah - the old was passing away and all was being made new. I was convinced that He was allowing for the potential that ALL that He was delivering HAD to be placed into an entirely NEW context - that the new cloth and new wine was of His making and that it could not be forced upon the structure, economy, model, law or covenant of the Old Testament. It HAD to be wiped away and replaced. I couldn't have been more wrong about the passages or what was being taught here. Why?
First off, it completely violated his earlier imminently clear words...
'Do not think that I have come to destroy the LAW or the PROPHETS, I have not come to destroy, but to fulfill.'
Secondly, it doesn't fit the context...
[before I move into these comments, I am going to state my assumption that these are two descriptions of the SAME set of conversations - one with the Pharisees and the other with John's disciples. Both being in the same place and conversation, at the same time, seeing that both passages cite both conversations.]
1) 'I desire mercy and not sacrifice' ... In response to His sitting and eating with 'sinners and tax collectors' (against which nothing in the scriptures is ever stated) Yeshua quotes Hosea 6:6, which is clearly a citing of a longstanding principle of the Covenant. Yeshua suggested that they go back and learn what this means... 'I desire the knowledge of Elohim more than burnt offerings'. Heartless perfunctory performances of religion are never acceptable. Cain did that much. It wasn't acceptable then, not in Hosea's day, not in Yeshua's days, not in ours. The Pharisee's added to the Torah something that not only wasn't there...it was forbidden - heartlessness towards outsiders. This was an interjection of tradition.
2) John's disciples and fasting... This question did not suggest that they were doing wrong, or had heartless motives; however, it exposed their sincere desire to learn the ways of Yeshua. Their practice of fasting was not based upon a prescription from Moses, it was founded upon the traditions of the group from which John likely drew his disciples - the careful, conscientious keepers of Qumran - the Zadokites or Essenes.
Both groups: the 'out-and-about, in-your-face pharisees' and the introspective "guardians of the law" Zadokites had the same practice of placing hedges around the Law (rules to prevent you from breaking the laws of Moses) even though each had vastly different motivations.
Where does this relate to the passages at hand? These two groups were the ones ADDING and re-purposing - not Messiah.
What He is gently stating here is now quite clear and simple to me. Adding to the Covenant, adding to the Regulations, the Statutes or the Laws is wrong - even if it is for the right reasons. Traditions have no place ahead, among or in place of what has been delivered, and when these new practices or traditions are attached to the beloved and comfortable garment, or the wineskin , then you risk rending the cloth or bursting the wineskin. We are not to do this, we are not to add tradition to revelation.
We spent years in a tradition of Christianity that boasted of their 'regulative principles' for worship - how every aspect of their tradition was based upon scripture. They couldn't have been farther from the truth - it was tradition masquerading as revelation, and to elevate tradition over revelation is idolatry.