God had tolerated rebellion and idolatry in Israel since 997 B.C.E. The rebellious Northern Kingdom did not last three hundred and ninety years. When it was destroyed in 740 B.C.E. this served as a direct punishment for its departure from the worship of Jehovah as God. But it did not settle the matter as far as Jehovah was concerned. There was still a measure of accounting to be settled with the mother capital, Jerusalem. Therefore, Jehovah went on to instruct Ezekiel:

“And you must lie upon your right side in the second case, and you must carry the error of the house of Judah forty days. A day for a year, a day for a year, is what I have given you. And to the siege of Jerusalem you will fix your face, with your arm bared, and you must prophesy against it. And, look! I will put cords upon you that you may not turn yourself from your one side to your other side, until you will have completed the days of your siege.”​—Ezek. 4:6b-8.

If Ezekiel was lying (belly down) with the head to the east in his mimic siege of Jerusalem, then his left side would be to the north, the direction of the former Northern Kingdom of Israel, and his right side would be to the south. So it was fitting for him to lie upon his right side when carrying the “error” of the Southern Kingdom of Judah. He would thereby be placing all the burden on his right side. Of course, Ezekiel’s lying on his right side for forty days came after his lying on the left side for three hundred and ninety days, which would mean four hundred an thirty days of lying down as in a siege.*