You are also focusing just on "was it against the Mosaic Law"
So is Christ in Mark 7:7-13 - have you read it?
Note the title of this thread - if you would like second reason for such a focus on this particular thread.
instead of on the question "why did Jesus gave this instruction".
Already answered it -
Jesus did NOT give any instruction at all against Law.
And in Matt 5 He condemns the idea that people would accuse Him of such a thing.
17 “
Do not presume that
I came to abolish the Law or the Prophets; I did not come to abolish, but to fulfill. 18 For truly I say to you, until heaven and earth pass away,
not the smallest letter or stroke of a letter shall pass from the Law, until all is accomplished! 19 Therefore,
whoever nullifies one of the least of these commandments, and teaches others
to do the same, shall be called least" Matt 5
Your question was a bit flawed as Jesus's Matt 5 statement points out.
It was like "when did you stop beating your dog" asked to someone who never beat their dog. Then when it is pointed out that they never did that you respond "you need to focus". Were we simply not supposed to notice.
Why did Jesus gave the instruction to the man to take his mat and walk
Because the man was out in the open and now that he was healed -- needed to go home and be at rest.
And of course - it was no sin to do that even on the Sabbath - carrying one's "mat" and heading home.
through the city with it,
Why not?
No actual scripture says "you can carry your blanket home on Sabbath as long as you don't walk through town".
when it was not allowed to do on Sabbath?
Not allowed by?
It was already pointed out in the posts you ignore that no such command was given in the Bible
#42 #57
In Acts 10:28 Peter claims it was "against the Law" for a Jew to keep company with a gentile
28 Then he said to them, “You know how unlawful it is for a Jewish man to keep company with or go to one of another nation.
- when in fact that law was not in scripture but rather in the "traditions" of Jews at that time. One cannot blame God for laws that others make up.
Your response seems to indicate that you want this point repeated .