A congregation is a group of people who gather together, especially for religious purposes. In the Bible, God called the people of Israel "the congregation of the Lord" because they had a special agreement (covenant) with God. The entire nation of Israel was considered to be God's people (Exodus 3:6–8, 15–16; 12:6; Isaiah 1:2–4; 14:1).
As a chosen nation, Israel was to show God's greatness to other nations (Deuteronomy 4:6–14; Isaiah 42:1; 45:4; 65:9, 22). So, the nation was called “the whole assembly of the congregation of Israel” (Numbers 14:5; see also Leviticus 4:13; Numbers 16:3).
The New Testament church builds on the spiritual foundation set by the Old Testament congregation of God's people. Several passages in the Bible show this connection between the church and God's people in the Old Testament (Hebrews 2:10–13; 1 Peter 2:9–10; see also Romans 9:1–8; Galatians 6:16).