Judges 1:3

And Judah said unto Simeon his brother The personification of a tribe or nation is common in O.T. idiom, e.g. Judges 11:17; Numbers 20:14; Joshua 17:14 etc.; hence the tribal traditions often take the form of narratives about individuals. Judah and Simeon were both Leah-tribes, Genesis 29:33 ff. Owing to this tie of kinship, and still more to the fact that it was never strong enough to maintain itself as a distinct tribe, Simeon became merged in Judah. Its settlements were in the south, within the territory of Judah, Joshua 19:1-7; in Joshua 15:26-32; Joshua 15:42 these are even reckoned as Judahite. In Genesis 34,; cf. Genesis 49:5-7, Simeon appears in close alliance with Levi, also a -brother" of the Leah-family; they attempted to settle in Shechem, but their treachery and violence ended only in disaster to themselves; Levi's career as a -secular" tribe came to an end, and Simeon fell into a subordinate position. Though the date and context of this incident cannot be fixed with certainty, it probably comes within the present period.

my lot The word implies a partition of the land by means of the sacred lot before the invasion; this would have taken place at the sanctuary (probably Gilgal) where the divine oracle was consulted, Judges 1:1; cf. Joshua 17:14; Joshua 17:17; Joshua 18:6 JE. Perhaps some account of the allotment stood originally at the beginning of this document; traces of it may be preserved in Joshua 14:6 ff; Joshua 15:1 ff. (Judah), Judges 16:1 ff. (Joseph).

Simeon went with him To reach his lot Simeon would have to pass through the territory of Judah.