Some time ago, I looked up the "sealed" in Ephesians 1:13 -- "you were sealed with that holy Spirit of promise" -- and the "mark" of the Beast in Rev. 13:17 -- "no one could buy or sell unless he had the mark". Just to see what the difference was.
The seal of the Holy Spirit is like a maker's mark or stamp of quality put on a finished product. The mark of the beast is "charagma" in the Greek, which means a scratching or etching, or a mark of servitude.
IF you are willing & obedient , you shall eat the good of the land: But if you refuse & rebel, You shall be devoured with the sword: for the mouth of the LORD hath spoken it. Isaiah 1:19, 20