Abraham's most noteworthy sacrifices are described in Gen.Chs. 15 and Ch.22.
In Ch.15 Abraham is told to offer three animals, which were divided in half,
and two birds, which were not divided. According to the Midrash, the animals
symbolized the kingdoms that later ruled over the Hebrews (for example, the
bullock represents Egypt; see Jeremiah 46:20), and the birds represent Israel;
the dividing of the animals, but not of the birds, symbolizes the fact that
the Hebrews would survive being subjugated by the kingdoms. In fact, the
Egyptian subjugation was described to Abraham in a vision at that time.
In Ch.22 Abraham is told to sacrifice his son Isaac. He obeys, but just
before he does it he is stopped, and he sacrifices a ram instead. The ram
was caught by its horns in the bushes; they symbolize the horns that were
blown at the time of the revelation on Mt.Sinai (Ex.Ch.19) and at the time
of the return from exile (Isaiah 27:13).
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