I found The Lovers' Tasks
(or "The Elfin Knight") in 80 English Folk Songs
collected by Cecil Sharp & Maud Karpeles during the years 1916 to 1918. I really love this song and much prefer it to the similar Scarborough Fair
as I find it more tuneful and the lyrics more intriguing.
I used to love singing this song with Kerstin Knie whereby we would share the verses on a gender basis. The song is of lovers giving each other impossible tasks to perform, the tasks being preconditions for love and marriage.
When with Das Trio
it would be sung by Maike Weyerts while I accompanied her on my concertina..