The interpretation timeline

Ps 99:2

How this passage has been read — the sources, oldest to newest.

From the early Church Fathers to now.

2 Patristic · 1 Jewish

Ps 99:2 · Douay-Rheims
“Sing joyfully to God, all the earth: serve ye the Lord with gladness. Come in before his presence with exceeding great joy.”
Patristic before A.D. 750
430
A.D.
Augustine of Hippo Patristic
A.D. 354–430
“"O serve the Lord with gladness" (ver. 2): he addresseth you, whoever ye are who endure all things in love, and rejoice in hope. "Serve the Lord," not in the bitterness of murmuring, but in the "gladness of love." "Come before His presence with rejoicing." It is easy to rejoice outwardly: rejoice before the presence of God. Let not the tongue be too joyful: let the conscience be joyful. "Come before His presence with a song."”
Source
457
A.D.
Theodoret of Cyrus Patristic
c. A.D. 393–457
“"Serve the Lord with gladness," for the kingship of our God and Savior has nothing of the harsh tyranny of the devil; rather, his lordship is mild and loving.”
648 years pass — nothing from this stretch is hosted yet
Scholastic c. 1100 – 1500
1105
A.D.
Rashi Jewish
1040–1105
“Serve the Lord with joy Now why so much? You should know the Lord is God, Who recompenses you with reward for your work, but the heathens need not worship with joy because their deities do not give them any reward.”
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.