It is!

The quote is from the Book of Mormon. It refers to a vision that Nephi saw of Mary the mother of Jesus:
1 Nephi 11:
13 And it came to pass that I looked and beheld the great city of Jerusalem, and also other cities. And I beheld the city of Nazareth; and in the city of Nazareth I beheld a virgin, and she was exceedingly fair and white.
14 And it came to pass that I saw the heavens open; and an angel came down and stood before me; and he said unto me: Nephi, what beholdest thou?
15 And I said unto him: A virgin, most beautiful and fair above all other virgins.
In the Bible, whitens is associated with beauty, as well as with purity and holiness:
Psalms 51:
7 Purge me with hyssop, and I shall be clean: wash me, and I shall be whiter than snow.
Song of Solomon 5:
10 My beloved is white and ruddy, the chiefest among ten thousand.
Lamentations 4:
7 Her Nazarites were purer than snow, they were whiter than milk, they were more ruddy in body than rubies, their polishing was of sapphire
Daniel 11:
35 And some of them of understanding shall fall, to try them, and to purge, and to make them white, even to the time of the end: because it is yet for a time appointed.
Daniel 12:
10 Many shall be purified, and made white, and tried; but the wicked shall do wickedly: and none of the wicked shall understand; but the wise shall understand.
Revelation 19:
8 And to her was granted that she should be arrayed in fine linen, clean and white: for the fine linen is the righteousness of saints.
zerinus