We used to sing this old hymn called “Whiter Than Snow”.

WHITER THAN SNOW
Lyrics by James Nicholsen
Tune by William G. Fischer

Chorus:
Whiter than snow, yes, whiter than snow
Now wash me and I shall be whiter than snow


What could ever be whiter than snow?
There is a Greek word which has been translated as ‘white’ which is whiter than snow. . .
G2986
lampros -radiant; by analogy limpid; figuratively magnificent or sumptuous (in appearance): - bright, clear, gay, goodly, gorgeous, white.


Let us be glad and rejoice, and give honour to him:
for the marriage of the Lamb is come,
and his wife hath made herself ready.
And to her was granted that she should be arrayed in fine linen,
clean and white-G2986 lampros
Revelation 19:7-8 KJV