When did Hashem erase Yisrael's sins?
Rashi: In Egypt and in the Midbar - also now, repent to Me!
What is the comparison to a cloud?
Radak: Just like a cloud is dissolved in water, so I erased your sins.
Radak citing Ibn Ezra: Like a cloud passes when the sun comes out.
Malbim: Your sins divide between you and your G-d. I cannot put My Shechinah among you. Your sins are like a cloud that darkens and blocks the sun's rays. I will erase them, just like wind scatters clouds. Pesha'echa (sins of rebellion) are like a thick cloud; Chatos'echa (Shogeg) are like a thin cloud that does not darken so much.
Did Hashem already redeem you?
Radak: He will redeem you now from Bavel.
Malbim: If you will repent, I already redeemed you, for the Ge'ulah is prepared; it depends on Teshuvah.
