because they had been unfaithful to the LORD
The unfaithfulness mentioned here refers to the idolatry and abandonment of the covenant with God by the people of Judah. This spiritual infidelity was a recurring theme in the history of Israel and Judah, often leading to divine judgment. The covenant relationship required exclusive worship of Yahweh, and deviation from this was seen as a breach of faith. This unfaithfulness is reminiscent of the warnings given in Deuteronomy 28, where blessings and curses are outlined based on Israel's obedience or disobedience.

Shishak king of Egypt
Shishak, also known as Sheshonq I, was the founder of the 22nd Dynasty of Egypt. His reign is historically corroborated by Egyptian records, including a relief at the Karnak Temple that lists his conquests in Israel and Judah. Shishak's campaign against Jerusalem is one of the earliest events in the Bible that can be directly correlated with external historical records, providing a significant archaeological link.

attacked Jerusalem
The attack on Jerusalem by Shishak was a significant event, as it demonstrated the vulnerability of Judah due to their spiritual and political failings. This invasion resulted in the plundering of the temple and the royal palace, as described in the subsequent verses. Theologically, this attack can be seen as a fulfillment of the covenant curses for disobedience. It also serves as a reminder of the need for reliance on God rather than political alliances or military strength. The event foreshadows later sieges of Jerusalem, including those by the Babylonians, and highlights the recurring theme of divine judgment and mercy throughout the biblical narrative.

“​In the fifth year of Rehoboam’s reign…” (2 Chron 12:2)

• The writer fixes the moment with precision. Five years after Solomon’s death, Judah is already feeling the cost of turning from the Lord. 1 Kings 14:25 confirms the exact same dating, underscoring the historical reliability of the account.

• The first three years of Rehoboam had looked promising—“they walked in the ways of David and Solomon for those three years” (2 Chron 11:17)—but the next two years show how quickly a nation can drift when leaders and people neglect God’s Word (Deuteronomy 17:18-20; Psalm 119:9).

• The timing reminds us that God is patient, yet He will not indefinitely allow rebellion to go unchecked (Ecclesiastes 8:11; 2 Peter 3:9-10).

“…because they had been unfaithful to the LORD…”

• Scripture states the cause plainly: spiritual unfaithfulness—not military weakness—opened the gate. This fulfills the warning Solomon heard at the temple dedication: if the king or people “turn away” the Lord would “uproot” them (2 Chron 7:19-22).

• Their unfaithfulness included idolatry and adopted pagan practices (2 Chron 12:1; 1 Kings 14:22-24). The covenant laid out in Deuteronomy 28:47-52 promised foreign invasion when Israel served other gods.

• The same pattern appears throughout Judges: “He handed them over to raiders who plundered them” (Judges 2:14). National sin always carries national consequences (Proverbs 14:34; Galatians 6:7-8).

• God’s motive is corrective, not merely punitive. As later verses show, the invasion prompts humility (2 Chron 12:6-7), illustrating Hebrews 12:6—“the Lord disciplines the one He loves.”

“…Shishak king of Egypt attacked Jerusalem.”

• Shishak (Sheshonq I in Egyptian records) was the very ruler who had once sheltered Jeroboam during Solomon’s reign (1 Kings 11:40). The political alliance Judah might have expected now turns into an assault, highlighting that trust placed in foreign powers rather than in the Lord is futile (Isaiah 31:1).

• God uses Shishak as His instrument of discipline. Later verses record the loss of the temple treasures and Solomon’s gold shields (2 Chron 12:9), a tangible reminder that earthly splendor cannot substitute for covenant loyalty (Matthew 6:19-21).

• The attack stops short of annihilation. “Nevertheless, they will become his servants so that they will learn the difference between serving Me and serving the kingdoms of the earth” (2 Chron 12:8). Even judgment is tempered by mercy (Lamentations 3:31-33).

• Historically, Egyptian reliefs at Karnak list towns in Judah conquered by Sheshonq I, corroborating the biblical record and demonstrating that Scripture’s historical claims stand firm.

2 Chronicles 12:2 teaches that God’s covenant people cannot compromise with sin without consequence. Five short years after Solomon’s kingdom divided, Judah’s unfaithfulness invites divine discipline through Shishak’s invasion. The verse ties political events directly to spiritual reality: when God’s people abandon Him, He may permit foreign powers to humble them so they will seek Him anew. Faithfulness brings security; unfaithfulness opens the door to loss—yet even God’s judgment carries the purpose of restoration for those who repent.

In the fifth year of king Rehoboam.--The order of events is thus given: For three years Rehoboam and his people continued faithful to the Lord (2Chronicles 11:17); in the fourth year they fell away; and in the fifth their apostacy was punished.

Shishak.--The Sesonchis of Manetho, and the sh-sh-nk of the hieroglyphs, was the first king of the 22nd dynasty. "His name," says Ebers, "and those of his successors, Osorkon (Zerah) and Takelot, are Semitic, a fact which explains the Biblical notice that Solomon took a princess of this dynasty for his consort, and stood in close commercial relations with Egypt, as well as, on the other hand, that Hadad the Edomite received the sister of Tahpenes the queen to wife (1Kings 11:19). In the year 949 B.C. Shishak, at the instigation of Jeroboam, took the field against Rehoboam, besieged Jerusalem, captured it, and carried off a rich booty to Thebes. On a southern wall of the Temple of Karnak, all Palestinian towns which the Egyptians took in this expedition are enumerated" (Riehm's Handwort. Bibl. Alterth., p. 333).

Because they had transgressed.--For they had been faithless to Jehovah. This is the chronicler's own parenthetic explanation of the event, and expresses in one word his whole philosophy of Israelite history. Of course it is not meant that Shishak had any consciousness of the providential ground of his invasion of Judah.