Sealed or Marked in the forehead?

Ephesians 1:13 KJV

 In whom ye also trusted, after that ye heard the word of truth, the gospel of your salvation: in whom also after that ye believed, ye were sealed with that holy Spirit of promise,

Revelation 7:3 KJV: 

Saying, Hurt not the earth, neither the sea, nor the trees, till we have sealed the servants of our God in their foreheads.

Revelation 13:16-17 KJV

16 And he causeth all, both small and great, rich and poor, free and bond, to receive a mark in their right hand, or in their foreheads:

17 And that no man might buy or sell, save he that had the mark, or the name of the beast, or the number of his name.