The use of the word "evil" in the OT is extremely problematic. The same root gets used for every connotation from "bad" to "harmful" to "unfortunate" to "wicked" (disobedient). Regardless:
Ge 6:5
Then the LORD saw that the wickedness of man was great on the earth, and that every intent of the thoughts of his heart was only evil continually.
Ge 8:21
The LORD smelled the soothing aroma; and the LORD said to Himself, "I will never again curse the ground on account of man, for the intent of man's heart is evil from his youth; and I will never again destroy every living thing, as I have done.
No pomp or ritual is necessary.
By the way, evil is not the same thing as sin. Lev 4 makes it pretty clear that sin is something which is unintentional, and only realized by the actor after the fact. Both the Old and New Covenants address sin, not evil.