There is a difference between the twelve tribes of Israel and the twelve sons of Israel. “Israel” is the name that God gave Jacob (Genesis 32:28). His twelve sons are Reuben, Simeon, Levi, Judah, Dan, Naphtali, Gad, Asher, Issachar, Zebulun, Joseph, and Benjamin (Genesis 35:23-26; Exodus 1:1-4; 1 Chronicles 2:1-2). When the tribes inherited the Promised Land, Levi’s descendants did not receive a territory for themselves. Instead, they became priests and had several cities scattered throughout all of Israel. Joseph did not receive a tribe, either—Jacob had adopted Joseph’s two sons, Ephraim and Manasseh, essentially giving Joseph a double portion for his faithfulness in saving the family from famine (Genesis 47:11-12). This makes the tribes as listed in Joshua: Reuben, Simeon, Judah, Dan, Naphtali, Gad, Asher, Issachar, Zebulun, Benjamin, Ephraim, and Manasseh. Adding to the confusion, the tribe of Ephraim is sometimes referred to as the tribe of Joseph (Numbers 1:32-33).
After King Solomon died, Israel split into two kingdoms. Judah, to the south, included Judah, Simeon, and Benjamin. The other tribes combined to make the kingdom of Israel in the north. Israel was destroyed by the Assyrians, and most of the Israelites were either killed or deported; the Israelites who remained most likely integrated with the kingdom of Judah.
Jesus was from Judah, Paul was from Benjamin, and John the Baptist was a Levite, but, since the diaspora in A.D. 70, identifying the tribe of a modern Jew is a little more difficult. That doesn’t mean that the tribal divisions are irrelevant. During the tribulation, when most of the world has abandoned God and is following the Antichrist, 144,000 Jews will be sealed by God. This number comprises 12,000 from each tribe. So, even if we don’t know who is in what tribe, God has kept track. The tribes are listed again in Revelation 7:5-8, but they are not the same tribes that were given land in Joshua. Manasseh is there, and Ephraim (under Joseph’s name). But instead of Dan, Levi is included. No explanation is given as to why.