But why? Can you comprehend and explain this?
When the Law expresses the very will and word of God? When the Law is inspired, holy, and good, and reveals the Godly righteous moral standards to mankind?
What is the biblical answer to this?
Why has it been deemed weak, miserable and worldy?
It's about the 'hedging around the Law.' the post-exilics (nehemiah, ezra, others later) saw the lesser dietary/ceremonial commands as protection against breaking the weightier. So they made many, many rules. Notice how Nehemiah immediately stops inter-racial marriage. The Pharisees have sometimes been called the broken nose sect because they would block their vision in the marketplace so as not to see women and get attracted, leading to crashing into posts and corners of buildings! Thanks to the 'hedge.'
2nd, it is the human factor trying to fulfill it. Details on that are found in Col 2--they have no power in restraining sensuality, he says about the neo-Judaism that also called christians 2nd rate. God had Christ come and fulfill the law (Rom 10:1-4), so that there is a great basis for fellowship that prevents favoritism and 'deadens' selfish desires. That's what makes the new covenant new--it is not a human party at this end; it is Christ (in arrangement with God at 'that' end), but Christ on our behalf, as our representative. A new man.
3rd, the same basic rules have been used around the world to try to obligate God to humans. See the comparative list in Lewis' "Illustrations of the Tao" in the back of ABOLITION OF MAN. All human religion has that thought of human obedience making God obligated to us, rather than Christ's work making us enjoy honoring him, which is empowering. The other is disappointing.
Hebrews captures yet another miserable feature: the sacrifice system was 'only an annual reminder of sins.' Incredibly enough, I have seen accounts of 'tabaski' (annual forgiveness ritual) from primitive Islamic cultures around Africa, where an animal is sacrificed to start the ritual, and the person starts out the day griping about the sins of everyone around them including ancestors. Talk about weak and miserable. The ritual is supposed to cure it, but the next day they are the same.