(taken from Archaeological Study Bible)
1) The Hebrews kept extensive records of a family’s ancestory. These were used for practical and legal purposes: to establish a person’s heritage, inheritance, legitimacy and rights. Luke followed the traditional approach of tracing lineage through males, but Matthew included five women (Bathsheba is not named but is described), three of whom were outsiders to Israel.
2) In the New Testament the word “generation” translates four Greek words, all having reference to descent: (1) genea, most frequently found in the Synoptic (or parallel) Gospels (Matthew, Mark and Luke), signifying the lines of descent from an ancestor (e.g., 1:17); all the people living in a given period (e.g., 11:16); a class of people characterized by a certain quality (e.g., 12:39); or a period of time (Ac 13:36; Col 1:26); (2) genesis, in Matthew 1:1, in a heading to verses 2:17, used to mean “genealogy;” (3) genncma, in the phrase “brood of vipers” (3:7; 12:34; 23:33; Lk 3:7); and (4) genos, meaning “race” (1 Pe 2:9; KJV “generation”).
3) Bethlehem (2:1), a village about 5 miles south of Jerusalem, is called “Bethlehem in Judea” to distinguish it from the town of Bethlehem about 7 miles northwest of Nazareth.
4) Originally a religious caste among the Persians, Magi were devoted to astrology, divination and the interpretation of dreams. This led to an extension in the meaning of the word, and by the first century B.C. the terms magi and Chaldean were applied generally to fortune tellers and to the exponents of esoteric religious cults throughout the Mediterranean world. “Magus” or “sorcerer” is the name given to Simon in Acts 8:9, to Bar-Jesus in Acts 13:6 and to Elymas in Acts 13:8. The legend of “the Three Kings” is late and medieval.
The Magi were likely from Persia or southern Arabia, both of which lay east of the Holy Land. Herod was “disturbed” (2:3) by the Magi’s announcement because he knew he was not the rightful heir to Israel’s throne, having usurped power by aligning himself with Rome. The Magi’s visit likely caused him to fear that invading forces from the east might join others within Israel to replace him with a king from the true line of the anticipated Messiah. The religious leaders had aligned themselves politically with Herod. If his power base were threatened, so was theirs.
5) The “star” (2:2) was probably not an ordinary star, planet or comet, though some interpreters have identified it with the conjunction of Jupiter and Saturn or with some other astronomical phenomenon.