A star symbolized a king (see Isaiah 14:12; Matthew 2:1–10). A scepter symbolized power and majesty (see Genesis 49:10; Psalm 45:6).
Historically, King David fits this description. The Moabites, whose defeat Numbers 24:17 mentions, were among the many peoples he conquered during David's rule (2 Samuel 8:2). Yet, Moab remained a threat to Israel after David's time (see 2 Kings 3:1–27; Isaiah 15–16; Jeremiah 48).
Many interpreters have extended this image beyond David. Christians identify Jesus of Nazareth with a star and a scepter (compare Matthew 2:2; 2 Peter 1:19; Revelation 2:28; 22:16; compare Hebrews 1:8).
the sons of Sheth: These people were probably the ancient Sutu, a group known from other records.
However, the name may refer to a different people group. It could refer to:
Edom, also called Seir, which David later defeated (Numbers 24:18),
Amalek, one of Israel’s earliest and most lasting enemies (24:20).