"Lord, I'm the True Vine" is one of the earliest recorded precursors of gospel music, recorded in 1930 by the otherwise unknown Eddie Head & Family.
"Lord, I'm the True Vine" sounds closer to the Carter Family or Blind Arizona Dranes than Thomas Dorsey, but you can hear the beginnings of gospel in the call and response of the two voices and the furiously strummed guitar.
2001_eddie_head_and_family_-_lord__i_m_the_true_vine.mp3
"Lord, I'm the True Vine" by The Gospel Sound, Volume 2, LP by Eddie Head and Family
Produced and edited by Kateleigh Mills.