Instead of harvesting, I thought the people in the hymn were herding sheep. "Bringing in the Sheep..."
A childhood belief about hymns

others believed things like this
- When he was a kid, my husband thought the hymn "bringing in the sheaves" was "bringing in the cheese."Anon
- As a young child I thought that sheep and poodles were the same animal.— Jane
- I use to think sheep shrank when it rained.Anon
- sheep were wooly pigs— CJ
- I used to believe that humans were a subspecies of sheep.Anon
- I used to believe that when sheep had their wool sheered off, they became lambds again.— Janet