18 The disjunctive vav (ו) is here introducing a circumstantial clause of time.
19 There is no verb “became” in this line. The second half of the line is introduced with the particle הִנֵה (hinneh, “look, behold”) in its archaic sense. This deictic use is intended to make the reader focus on Miriam as well.
20 The word “leprosy” and “leprous” covers a wide variety of skin diseases, and need not be limited to the actual disease of leprosy known today as Hansen’s disease. The description of it here has to do with snow, either the whiteness or the wetness. If that is the case then there would be open wounds and sores—like Job’s illness (see M. Noth, Numbers [], 95–96).
21 Heb “turned to.”

In other versions

ESVEnglish Standard Version

When the cloud removed from over the tent, behold, Miriam was leprous, like snow. And Aaron turned toward Miriam, and behold, she was leprous.

NIVNew International Version (2011)

When the cloud lifted from above the tent, Miriam’s skin was leprous—it became as white as snow. Aaron turned toward her and saw that she had a defiling skin disease,

CSBChristian Standard Bible

As the cloud moved away from the tent, Miriam’s skin suddenly became diseased, resembling snow. When Aaron turned toward her, he saw that she was diseased

NLTNew Living Translation

As the cloud moved from above the Tabernacle, there stood Miriam, her skin as white as snow from leprosy. When Aaron saw what had happened to her,

LEBThe Lexham English Bible

And the cloud departed from on the tent, and behold, Miriam was infected with a skin disease white like snow; when Aaron turned toward Miriam, behold, she was afflicted with a skin disease.

KJV 1900King James Version

And the cloud departed from off the tabernacle; and, behold, Miriam became leprous, white as snow: and Aaron looked upon Miriam, and, behold, she was leprous.

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