Jeremiah's original audience in Judah found it impossible to believe God would allow the destruction of Jerusalem, the city wherein He chose to dwell (Jer. 7:1–4). Ezekiel's original audience in Babylon, who had been carried away from the Holy City, should have found it easier to believe the Lord would impose the covenant curse of exile on His people. However, the old covenant community often missed God's lessons for them. Ministering at roughly the same time as Jeremiah, Ezekiel had to take dramatic steps to convince the Jews in Babylon that Jerusalem would be razed for its impenitence.
Today's passage records some of the most drastic actions Ezekiel performed to impress his message upon the people. We read of the prophet, under the Lord's direction, etching the city of Jerusalem on a brick and setting up siegeworks around it (Ezek. 4:1–3). Archaeological discoveries indicate that ancient Near Eastern peoples commonly engraved city plans on bricks, so that is likely what Ezekiel did. The prophet's lesson was plain: God would send foreigners to capture Jerusalem and burn it to the ground.
Verses 4–8 describe how Ezekiel was commanded to lie down on his side in plain view of his original audience. First, he lay on his left side for 390 days to "bear [Israel's] punishment" (vv. 4–5). Most scholars believe this represents the period from 976 BC, the approximate year in which the glory of the Lord entered the Jerusalem temple during Solomon's reign, until Jerusalem's fall in 586 BC. Israel's idolatry received official court sanction under Solomon, whose foreign wives brought their false religions to Israel (1 Kings 11:1–8). Thus, Ezekiel's action represented God's charge against His people that their four hundred years of wanton idolatry merited their exile. After 390 days on his left side, Ezekiel lay on his right side for forty days (Ezek. 4:6–8). Ezekiel's lying on his right side was likely symbolic not of forty years exactly but of one generation. An Old Testament generation is forty years long (Num. 32:13), so the prophet's action revealed that the exile would last long enough for one generation of Jews to pass away.
Finally, Ezekiel 4:9–17 describes the meager diet the prophet was to eat while lying on his side, for twenty shekels is but eight ounces of food (v. 10). This depicts limited rations consumed during siege conditions, which Ezekiel's actions demonstrated were soon to come for Jerusalem. The holy God was about to judge His unholy people.
Church leaders are tasked with maintaining the purity of the church in this new covenant age (1 Cor. 5). This is accomplished by the careful practice of church discipline, which must lead finally to excommunication for those who remain impenitent. The ancient Israelites and Judahites did not maintain discipline and cast idolaters out of their midst, so God judged them. Our Creator will likewise hold churches accountable that fail to discipline their members appropriately.