Hebrews 9:15-17

15Therefore he is the mediator of a new covenant, so that those who are called may receive the promised eternal inheritance, since a death has occurred that redeems them from the transgressions committed under the first covenant.

16For where a will is involved, the death of the one who made it must be established.

17For a will takes effect only at death, since it is not in force as long as the one who made it is alive.