Kabbalah zu Schir haSchirim 5:2

"And the men of the place asked him of his wife; and he said, 'She is my sister" (Gen. 26:7), that is, just like Abraham said. For the Shechinah was with Isaac and his wife, and he said of the Shechinah, as it is written, "Say to wisdom, 'you are my sister'" (Mishlei 7:4). Thus, he was strengthened and said, "She is my sister." Abraham and Isaac deserved (to say this). This is assuredly so because of the verse "My sister, my love, my dove, my undefiled" (Shir Hashirim 5:2). (They) were therefore worthy of saying "She is my sister." Thus, the Righteous were strengthened by the Holy One, blessed be He.

“…For my head is drenched with dew….” (Song of Songs 5:2). What is “drenched with dew”? And the Holy One, Bless be He said, you may think that, from the day that the Holy Temple was destroyed, I entered my house and dwelling place, but it is not so. I will not enter as long as you are in exile. Here is your sign, “My head is drenched in dew”. הא is the Shechinah in exile, her completion and her life is “dew” טל, which is יוד-הא-ואו and the letter values sums up to 39 טל, dew. It fills up the Shechinah from the source of all the supernal emanations. The Faithful Shepherd immediately rose with the holy patriarchs along with him. Up to this point is the secret of the unification. From here on the first portion of the concealed Torah.

…For my head is drenched with dew….” (Shir Hashirim 5:2). What is “drenched with dew”? And the Holy One, Bless be He said, you may think that, from the day that the Holy Temple was destroyed, I entered my house and dwelling place, but it is not so. I will not enter as long as you are in exile. Here is your sign, “My head is drenched in dew”. הא is the Shechinah in exile, her completion and her life is “dew”, which is יוד-הא-ואו (YOD-HE-VAV) and the letter values sums up to 39 טל, dew. It fills up the Shechinah from the source of all the supernal emanations. The Faithful Shepherd immediately rose with the holy patriarchs along with him. Up to this point is the secret of the unification. From here on the first portion of the concealed Torah.