In the book of Judges, the tribe of Judah is portrayed positively and the tribe of Benjamin is portrayed negatively. There are several reasons for this beyond the obvious Saul from Benjamin/David from Judah tension – the main reason is that’s what God had established as his desire. No king of Israel was ever supposed to come from the tribe of Benjamin. Way back in Gen. 49 God explained;
“The scepter shall not depart from Judah, nor the ruler's staff from between his feet, until tribute comes to him; and to him shall be the obedience of the peoples (Gen. 49:10).
Holding the scepter is the royal privilege of a king, and the king of Israel was to come from the favored tribe of Judah. Judah consistently emerges as a leader among the tribes.
When it was time to fight in the land, it was Judah, not Benjamin that was repeatedly selected by God to “go up first” (Judges 1:2; 20:18).
It was Judah, not Benjamin, that followed through capturing some of the most difficult land in Canaan. Judah was able to capture Gaza, Ashkelon and Ekron – cities that even Joshua never conquered (Josh. 13:1-4).
So, here’s the problem. Saul was their king for 40 years and he was from the tribe of Benjamin. It’s important to note that God never chose Saul as their king– God gave in to the incessant demands of Israel to have a tall and handsome king “like the other nations.” In so doing, they rejected God as their king. God summarized this in Hosea 13;
“10 Where now is your king, to save you in all your cities? Where are all your rulers— those of whom you said, “Give me a king and princes”? 11 I gave you a king in my anger, and I took him away in my wrath.
Ok, so with that background we’re better able to understand the seemingly obscure passage in Ezekiel 4 where God tells Ezekiel to lay down on his left side for the guilt of Israel for 390 days (a day for each year of Israel’s sin). And then God tells Ezekiel to lay down on his right side for the guilt of Judah for 40 days (a day for each year of Judah’s sin).
So -what was “the sin” of Israel and Judah? It was having a non-Judean King. Saul (from Benjamin) was king for 40 years, so Ezekiel publicly demonstrated Judah’s sin by laying on his right side for 40 days.
The 390 days which represent 390 years of rebellion in Israel is a bit more complicated, but it goes back to 983 BC where Sheba led a rebellion in Israel against the God appointed Judean King by crying out; “We have no portion in David; we have no inheritance in this son of Jesse! Every man go home, O Israel” (2 Sam. 20:1). This same cry of rebellion was repeated when the kingdom split in 931 BC when Jeroboam (not of Judah) was the king of Israel (1 Kings 12:16).
God gave Ezekiel these bizarre instructions to illustrate to the people how they had sinned by appointed and/or followed a non-Judean kings.
The math works:
From Sheba’s rebellion (983 BC) to the 5th year of Jehoiachin’s reign (593 BC) was 390 years. God’s command to Ezekiel in chapter 4 to lay on his right side was pointed directly at Saul and Judah’s rejection of his desire to have kings come from Judah. His command to lay on his left side for 390 days was pointed directly at Israel’s rejection of his desire to have kings from Judah for 390 years.
So, there’s a reason that the tribe of Judah is favored in Judges and it all goes back to God’s plan for the kings of Israel to come from that tribe, and not Benjamin.
PS - I've attached a handy chart that explains what I'm talking about....