It should be explained that the multicolored coat symbolizes the beloved son, as implied from the wording of the scripture (Genesis 37:3): "Now Israel loved Joseph more than all his children, because he was the son of his old age; and he made him a coat of many colors." It is also a sign of the birthright, as stated in the Talmud (Baba Batra 123a): "What did Jacob see that made him take the birthright from Reuben and give it to Joseph?" This is based on the verse (1 Chronicles 5:1): "Now the sons of Reuben the firstborn of Israel (for he was the firstborn; but forasmuch as he defiled his father's bed, his birthright was given unto the sons of Joseph the son of Israel)." Therefore, the tribes were specifically jealous of the multicolored coat, because Jacob elevated Joseph above all his brothers to the status of the firstborn and beloved son through it.