Likutei Moharan, Part II 83:11/ליקוטי מוהר"ן·תנינא פ״ג:י״א

111 . Now, the topic of Israel’s spilled blood contains many lofty and hidden matters, be it blood spilled through embarrassment or other, actual spilled blood. For there are very many fallen souls which have no elevation except through the spilled blood of Israel; [that] of a great individual. In some cases, they have no elevation except through actual spilled blood.

2This is the concept of “willful-transgressions become like merits” (Yoma 86b) ; that through the embarrassment or spilled blood, the Divine Presence covers their blood with the aforementioned love. And this is the concept of “love covers over all transgressions,” as mentioned above. The willful-transgressions become like merits, and the fallen souls, which correspond to transgressions, are raised up. They are elevated and transformed into merits through the aforementioned covering blood with love (see Tikkuney Zohar, Tikkun #21).