Veneration of relics is not a heresy. And it is not anti-Scriptural. BTW, the veneration of relics is recorded in the earliest Christian texts (earlier than the Church established canon of New Testament) like for example martyrdom of Saint Policarp - from 86 AD.
You want Scriptural evidence of miracle-working holy relics of a saint? Here you are:
And Elisha died, and they buried him. And the bands of the Moabites invaded the land at the coming in of the year.
And it came to pass, as they were burying a man, that, behold, they spied a band of men; and they cast the man into the sepulchre of Elisha: and when the man was let down, and touched the bones of Elisha, he revived, and stood up on his feet.
Why the relics of saints are holy and miraculous? Becasue they are belong to bodies of living holy men who are standing before the throne of Creator.
You are confusing the post-scholastic bookish speculations of Luther and Calvin with the actual early Church.
And what's your problem with Martin Luther? Among other things, he rescued The Church from a pack of thieves, scoundrals, blackmailers and every other form of criminal lowlife known as the Clergy. The church of that time was an ecclesiastical whorehouse. Unfortunately they seem to be migrating back.........
I hear you on Elisha -- it's a one-time miracle recorded in the Bible. But you must also address the ancient Jewish and Christian tradition that God hid away the body of Moses to prevent it becoming a relic for later superstitious pilgrims.
BTW, the veneration of relics is recorded in the earliest Christian texts
Read the New Testament -- it records many early heresies! It's not at all surprising that various heresies popped up after the apostles died. Just because a heresy is old doesn't make it right. That's the problem with not recognizing something -- i.e., the canon of Scripture -- as a measuring rod for gauging what is wrong and what is right with tradition. There's nothing inherently wrong with tradition except where they conflict with Scripture.