Our heavenly inheritance, among other things, is an "eternal inheritance" (Hebrews 9:15), held jointly with Christ (Romans 8:17) and "all them which are sanctified" (Acts 20:32). We who are born again "by the resurrection of Jesus Christ from the dead" and "kept by the power of God" (1 Peter 1:3, 5) find such an inheritance described in today's verse.
First, we notice that our inheritance is incorruptible, or undecaying, immortal. Note how the same word is used in verse 23: "Being born again, not of corruptible seed, but of incorruptible, by the word of God." Therefore "lay up for yourselves treasures in heaven, where neither moth nor rust doth corrupt" (Matthew 6:20).
Second, it is undefiled, pure, uncontaminated by sin. Remember, Christ is "holy, harmless, undefiled, separate from sinners" (Hebrews 7:26), and so, evidently, is our inheritance.
Third, it fadeth not away. "And when the chief Shepherd shall appear, ye shall receive a crown of glory that fadeth not away" (1 Peter 5:4).
Lastly, our inheritance is reserved in heaven for us. Christ prayed, "Holy Father, keep [same word] through thine own name those whom thou hast given me, that they may be one, as we are" (John 17:11). Surely our inheritance is as secure as we are, guarded by none other than the all-powerful guard.
So we see that our inheritance cannot die, cannot be tainted by sin, will never fade, and cannot be lost. "I know whom I have believed, and am persuaded that he is able to keep that which I have committed unto him against that day" (2 Timothy 1:12). JDM