A Christian’s hope in the return of Christ will be a purifying agent, setting them apart from the world.
1 John 2:28–3:3
28 Now, little children, abide in Him, so that when He appears, we may have confidence and not shrink away from Him in shame at His coming.
29 If you know that He is righteous, you know that everyone also who practices righteousness is born of Him.
3:1 See how great a love the Father has bestowed on us, that we would be called children of God; and such we are. For this reason the world does not know us, because it did not know Him.
2 Beloved, now we are children of God, and it has not appeared as yet what we will be. We know that when He appears, we will be like Him, because we will see Him just as He is.
3 And everyone who has this hope fixed on Him purifies himself, just as He is pure.