Ithamar

For the bishop of Rochester, see Ithamar (bishop). In the Torah, Ithamar is mentioned as the youngest son of Aaron the High Priest. After the death of his two eldest brothers Nadab and Abihu, Ithamar served as a priest along with his elder brother, Eleazar. During the travels of the Israelites in the desert, Ithamar stood at the head of the children of Gershon and Merari, the carriers of the Tabernacle. He was also in charge of the work of the Levites in general. Ithamar and Eleazar are regarded as the direct male ancestors of all Kohanim.
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island of the palm-tree
  

(land of palms), the youngest son of Aaron. (Exodus 6:23) (B.C. 1491.) After the death of Nadab and Abihu, (Leviticus 10:1) Eleazar and Ithamar were appointed to succeed to their places in the priestly office. (Exodus 28:1,40,43; Numbers 3:3,4; 1 Chronicles 24:2) In the distribution of services belonging to the tabernacle, and its transport on the march of the Israelites, the Gershonites and the Merarites were placed under the superintendence of Ithamar. (Exodus 38:21; Numbers 4:21-33) The high priesthood passed into the family of Ithamar in the person of Eli, but for what reason we are not informed.
  

palm isle, the fourth and youngest son of Aaron (1 Chr. 6:3). He was consecrated to the priesthood along with his brothers (Ex. 6:23); and after the death of Nadab and Abihu, he and Eleazar alone discharged the functions of that office (Lev. 10:6, 12; Num. 3:4). He and his family occupied the position of common priest till the high priesthood passed into his family in the person of Eli (1 Kings 2:27), the reasons for which are not recorded. (See ZADOK.)