Some have misinterpreted the "tomb" as literally refers to the cemented rectangular graveyard box where coffins were enclosed or the literally graveyard it self which the dead will rise at the sound of the trumpet.

But the "tomb" here refers to our Mortal Bodies where the Spark of our Divinity was trapped,where our souls is buried on it,waiting for Christ to Saved our souls being imprisoned and buried on our "tombs" or mortal bodies..to raise up from the graveyard (Mortal Body/tomb) our soul has been buried...

We will arise from our "tombs"(mortal bodies) into Life (Life Eternal)...

Tombs(Mortal Bodies) = Death..it has no"Life" at all because Mortal life has "death",mortal body is subjected to "death" and sufferings....Thus we are "living dead" on this mortal body of ours.

"the dead will rise from their tombs" - that is,we who are "living dead" will arise from our Mortal Bodies(tomb) into the real true LIFE...

Real True LIFE has NO DEATH....for LIFE IS ETERNAL...