What does Psalm 100:1 mean?

The psalmist calls upon the entire world to shout joyfully to God. The universal nature of this call is no accident. The LORD, God of Israel, is not some imaginary or tribal deity. He is the one and only God who made heaven and earth and deserves to be praised by all people. Although God chose the nation of Israel for special purposes, He also loves the whole world (John 3:16). He has provided evidence of Himself and His love in nature and in the Scriptures (Romans 1:18–20; John 5:39–40; Psalm 19).

After rising from the dead, Jesus commissioned His disciples to preach the gospel to the whole world (Matthew 28:18–20). The entire population of mankind has not yet turned to God and praised Him as the writer of this psalm desires. However, someday, the saved from every country, language, people group, and ethnicity will praise Him. Revelation 7:9–10 pictures this innumerable crowd of redeemed people shouting, "Salvation belongs to our God who sits on the throne, and to the Lamb!"