Jacob wished to cross the ford of the Jabbok, and he was detained there. The angel said to him: Didst thou not speak thus—"Of all that thou shalt give me I will surely give a tenth unto thee" (Gen. 28:22)? What did our father Jacob do? He took || all the cattle in his possession which he had brought from Paddan-Aram, and he gave a tithe of them amounting to 550 (animals).
Hence thou mayest learn that all the cattle in the possession of our father Jacob, which he had brought from Paddan-Aram, amounted to 5500 (animals). Again Jacob wished to cross the ford of the Jabbok, but he was hindered here. The angel said: Didst thou not speak thus—"Of all that thou shalt give me I will surely give a tenth unto thee" (ibid.)? Behold, thou hast sons.
Thou hast not given a tithe of them. What did Jacob do? He put apart the four firstborn children of the four mothers, and eight children remained. He began (to count) from Simeon, and finished with Benjamin, who was still in his mother's womb.
Again he began (to count) from Simeon, and he included Benjamin, and Levi was reckoned as the tithe, holy to God, as it is said, "The tenth shall be holy unto the Lord" (Lev. 27:82).