Yes, that's a great rendition of "I Will Arise" on "Sharon Mountain Harmony" but I confess that I first learned the song as a "Cradle Hymn" from Ruth Crawford Seeger's American Folk Songs for Christmas. In that guise it goes:

Hush my babe, lie still and slumber,
Holy angels guard thy bed.
Heavenly blessings without number
Gently stealing on thy head.

How much better art thou attended
Than the Son of God could be
When from heaven he descended
And became a child like thee.

Soft and easy is thy cradle,
Coarse and hard the Savior lay
When His birthplace was a stable
And His softest bed was hay.

The shape note arrangement of this tune is found in OSH (Original Sacred Harp) as "Restoration"; with chorus ("I will arise") and verses ("Come thy fount of every blessing") pretty much as Bill Destler sings them. And of course, with a repeated chorus, "I will arise" (and it is "will") goes on for a lot longer than the Cradle Hymn, so I was very happy to find it -- any excuse to extend a beautiful melody!

By the way, I was lucky enough to be at Pinewoods music camp the same year that Lucy Simpson (also on Sharon Mountain Harmony) was there. At mealtimes, it seemed like her table never stopped singing...