Revelation 14:9

And a third angel followed them, saying with a loud voice, If any one worship the beast and his image, and receive the mark on his forehead,

Revelation 14:11

And the smoke of their torment ascendeth for ever and ever: and they have no rest, day and night, who worship the beast and his image, and whosoever receiveth the mark of his name.

Matthew 26:52

Then said Jesus to him, Put up thy sword into it's place; for they that take the sword shall perish by the sword:

Treasury of Scripture Knowledge

Summary

And the LORD said unto him, Therefore whosoever slayeth Cain, vengeance shall be taken on him sevenfold. And the LORD set a mark upon Cain, lest any finding him should kill him.

Therefore

Set a mark, etc

Bible References

Therefore

Matthew 26:52
Then said Jesus to him, Put up thy sword into it's place; for they that take the sword shall perish by the sword:

Set a mark, etc

Revelation 14:9
And a third angel followed them, saying with a loud voice, If any one worship the beast and his image, and receive the mark on his forehead,