‘Numbers 21:9 relates that Moses made a bronze snake, elevated it upon a staff, and that anyone who looked upon it was healed of snakes bites (and it important to note in 2 Kings 18:4 that when the Israelites came to believe that the snake held in and of itself, it was destroyed. The Catholic Church has always stressed that relics hold no power inherently).”
One off, obviously, for Israel alone. Also shows the danger of idols - even from things God instructed them to make - let alone things people find on their own to idolize.
Clearly, nowhere is any Christian group told to make snake statues for healing.
“In 2 Kings 2:13, Elisha picked up Elijah’s cloak and took it away with him after the latter had been taken up, and God permitted a miracle to occur through the cloak.”
The miracle was from God. Elisha asked where the God of Elijah was and God answered. The mantle was symbolic of the authority of Elijah.
Nowhere are Christians taught or commanded to seek out mantles, nor to save them, nor to pass them on, nor that they hold any power.
“In 2 Kings 13:21, God performed a miracle through the bones of Elisha.”
These were not relics that were saved because of their powers. These were bones God used in this one instance to perform a miracle for His purposes.
“Acts 19:12 states that God performed miracles through cloaks and handkerchiefs that had been touched to Paul’s person.”
Nor does it encourage believers in Christ to do so, nor say they were saved, idolized, etc. Nor is it commanded. Nor is it taught by an Apostle.
“Post verses that say this is normative for believers in the Christian assembly.”
“Is this your way of dismissing Scriptural examples as one-offs?”
They were isolated instances in Scripture.
Never is it taught in Scripture.
Never is it commanded in Scripture.
The dangers are amply demonstrated by the instance you site in Numbers 21:9.
Finally...
“Sloppy. Catholics do not worship or idolize relics. Neither do we kneel before relics in and of themselves, but in reverence of God who graciously condescends to work through the object.”
Catholics routinely idolize relics, statues, etc. The internet has many pictures of such idolization.
You are no doubt familiar with this symbol:
It is relatively common, especially in the United States, to find the caduceus, with its two snakes and wings, used as a symbol of medicine. The modern use of the caduceus as a symbol of medicine became established in the United States in the late 19th and early 20th century.