Psalm 74:2 (ESV)

2 Remember your congregation, which you have purchased of old, which you have redeemed to be the tribe of your heritage! Remember Mount Zion, where you have dwelt.

The psalmist now reminds Yahweh of the days of old. The Hebrew word for this (“kedem”) is often used in the Bible to refer to the time between Abraham and the entrance into Canaan. In this time, Yahweh was Israel’s Maker, their Father who created them (Psalm 100:3; Isaiah 44:2; Hosea 8:14).

God claimed Israel for himself (Exodus 5:1; Exodus 6:5–7; Deuteronomy 32:8–9; Psalm 77:15; Psalm 78:35). Israel became Yahweh’s inheritance. Their position as inalienable possessions of the Lord was cemented when he freed them out of Egypt. Yahweh even came to live in Israel, first in a tent, and later in the temple, because he wanted to be close to his people.

Note that Israel is called a tribe in this verse (as opposed to the usual tribes). This is to indicate the special relationship between God and his people. Would Yahweh forget all of this and give up his inheritance? Asaph pleads in despair.