There are keys for good and there are keys for evil.

“And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven.” (Jesus Christ - Matthew 16:19)

“I am he that liveth, and was dead; and, behold, I am alive for evermore, Amen; and have the keys of hell and of death.” (Jesus Christ – Revelation 1:8)

“And to the angel of the church in Philadelphia write; These things saith he that is holy, he that is true, he that hath the key of David, he that openeth, and no man shutteth; and shutteth, and no man openeth…” (Jesus Christ - Revelation 3:7)

“And the fifth angel sounded, and I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit.” (Revelation 9:1)

The Bible on Generalities.

“For there are many unruly and vain talkers and deceivers, specially they of the circumcision: Whose mouths must be stopped, who subvert whole houses, teaching things which they ought not, for filthy lucre's sake. One of themselves, even a prophet of their own, said, the Cretians are alway liars, evil beasts, slow bellies. This witness is true.” (Titus 1:10-13)