1 Corinthians 15:51

(29) Behold, I shew you a (d) mystery; We shall not all sleep, but we shall all be changed,

(29) He goes further, declaring that it will come to pass that those who will be found alive in the latter day will not descend into that corruption of the grave, but will be renewed with a sudden change, which change is very necessary. And he further states that the certain enjoying of the benefit and victory of Christ, is deferred to that latter time.

(d) A thing that has been hid, and never known before now, and therefore worthy that you give good care to it.