Source? Non-Sequitur, the world's greatest (or at least it's most obsessive) authority on Jefferson Davis.
"We recognize the negro as God and God's Book and God's Law in nature tells us to recognize him - our inferior, fitted expressly for servitude. Freedom only injures the slave. The innate stamp of inferiority is beyond the reach of change. You cannot transform the negro into anything one-tenth as useful or as good as what slavery enables him to be." -- Jefferson Davis, March 1861
Source "Look Away: A History of the Confederate States of America" by William C. Davis, page 137