There is a lot of background information behind this song, but I’ll just say here that its most important purpose is to you let you feel that you are known and loved.
There is a considerable amount of musical “word-painting” in the song, sometimes in the vocal parts, and sometimes in the accompaniments. Word-painting is a technique in which the music reflects the literal meaning of the text. I won’t give away all of the instances in case you want to try to find them, but an obvious one is what the music does with the word “astray” – it goes astray from the established pattern.
A recording is playable with the video above (Choir: Anaheim East Chorale; Director: Larry Lowder; Piano: Beth Lillywhite; Organ: Darla Fulk).
The choral booklet sheet music that includes accompaniment for piano or harp and optional organ may be purchased here: https://www.jwpepper.com/The-Lord-Is-My-Shepherd/11575770.item .
A low-resolution version of the sheet music (4 pages - choir parts only and no artwork to save paper and ink) may be downloaded below. If you download the free choir part and do not purchase the complete score, I can e-mail the piano accompaniment if you contact me and let me know your plans for the song. Additionally, I have an arrangement available for piano plus harp.