1 Corinthians 15:51-53 (NKJV)  

51-  Behold, I tell you a mystery: We shall not all sleep, but we shall all be changed— 

52-   in a moment, in the twinkling of an eye, at the last trumpet. For the trumpet will sound, and the dead will be raised incorruptible, and we shall be changed. 

53-   For this corruptible must put on incorruption, and this mortal must put on immortality.