זוהר שמות — דף קפט ע”ב

Israel, children of the Holy King, descended to Egypt not only because of sin but because of the decree of the Covenant between the Pieces. The Holy One blessed be He wanted to make them like a rose growing among thorns — only what grows through hardship is chosen and gives forth its fragrance. When He wished to bring them out of Egypt, the thorns withered and were cast aside. After returning from Babylonian exile in shame, without miracles, they sinned again and the Holy Mother was exiled with them. Hence it is written: by your sins your mother was sent away, and the final redemption will come together with the Mother.