Arthur Chris Eccel argues that the theme of a choir in heaven in Mosiah 2:28 is evidence Joseph borrowed from the religious thought of the 19th century.
Arthur Chris Eccel, Mormon Genesis (Hilo, Hawaii: GP Touchstone, 2018), 195-96
Join the Choirs Above in Singing the Praise of a Just God
Mosiah 2:28, that I might go down in peace, and my immortal spirit may join the choirs above in singing the praises of a just God (cf. 1 Nephi 1:8; Mormon 7:7)
Psalms 148:1 Praise ye the LORD. Praise ye the LORD from the heavens; praise him in the heights. 2. Praise ye him, all his angels; praise ye him, all his hosts. 3. Praise ye him, sun and moon: praise him, and ye stars of light. 4. Praise him, ye heavens of heavens, and ye waters that be above the heavens.
Luke 2:13. And suddenly there was with the angel a multitude of the heavenly host praising God, and saying, 14. Glory to God in the highest, and on earth peace, good will toward men.
In the Bible, an angel (less commonly angels) is sent for specific purposes: to deliver a message, to protect, to destroy, to reap men or judgment, to gather the elect, etc. In Psalms 148, they are commanded to praise God, but apparently figuratively, since they are included with inanimate objects, such as stars and waters. This is reflected in the Hebrew word for angel, mal’akh, envoy, from a Semitic root “to send.” In the New Testament, the word angelos, envy, is a translation of the Semitic.
“Choir” does not occur in the Bible, and there is no mention of a group of angels singing, a “choir” (from Greek χορος [choros], a group of dancers or singers). At some point in the development of Euro-Christianity, the image of a “choir” of angels developed. Eventually, the angels were divided into various orders called choirs (9 choirs [orders] according to some, each with its function. Even so, in popular religion, this gave rise to the image of angels floating on clouds playing the harp. Whatever the meaning in this passage in Mosiah, this praise obviously comes from post-Biblical Euro-Christianity. The phrase is found in a hymn of Charles Wesley:
2. Thy will by me on earth be done, As by the choirs above,
Who always see thee on thy throne. And glory in thy love.
Contrast this with the Spurgeon sermon “Royal Homage” (no. 1102, 1873), “Nor can we expect that untrained voices should be admitted into the choirs above.”