a'-i (`ay, written always with the definite article, ha-`ay, probably meaning "the ruin," kindred root, `awah):
(1) A town of central Palestine, in the tribe of Benjamin, near and just east of Bethel (Genesis 12:8). It is identified with the modern Haiyan, just south of the village Der Diwan (Conder in HDB; Delitzsch in Commentary on Genesis 12:8) or with a mound, El-Tell, to the north of the modern village (Davis, Dict. Biblical). The name first appears in the earliest journey of Abraham through Palestine (Genesis 12:8), where its location is given as east of Bethel, and near the altar which Abraham built between the two places. It is given similar mention as he returns from his sojourn in Egypt (Genesis 13:3). In both of these occurrences the King James Version has the form Hai, including the article in transliterating. The most conspicuous mention of Ai is in the narrative of the Conquest. As a consequence of the sin of Achan in appropriating articles from the devoted spoil of Jericho, the Israelites were routed in the attack upon the town; but after confession and expiation, a second assault was successful, the city was taken and burned, and left a heap of ruins, the inhabitants, in number twelve thousand, were put to death, the king captured, hanged and buried under a heap of stones at the gate of the ruined city, only the cattle being kept as spoil by the people (Joshua 7; Joshua 8). The town had not been rebuilt when Jos was written (Joshua 8:28). The fall of Ai gave the Israelites entrance to the heart of Canaan, where at once they became established, Bethel and other towns in the vicinity seeming to have yielded without a struggle. Ai was rebuilt at some later period, and is mentioned by Isaiah (Isaiah 10:28) in his vivid description of the approach of the Assyrian army, the feminine form (`ayyath) being used. Its place in the order of march, as just beyond Michmash from Jerusalem, corresponds with the identification given above. It is mentioned also in post-exilic times by Ezra 2:28 and Nehemiah 7:32, (and in Nehemiah 11:31 as, `ayya'), identified in each case by the grouping with Bethel.
(2) The Ai of Jeremiah 49:3 is an Ammonite town, the text probably being a corruption of `ar; or ha-`ir, "the city" (BDB).