 He would develop this further in the co-authored book "Native American Theology".Tinker's recent work examines the historical and institutional controversy and surrounding an atrocity where a book of Christian history that was bound in the skin of an Indigenous Man and gifted to Iliff School of Theology.Although the human skin was removed and given to American Indian Movement representatives in the 1970s, a non-disclosure agreement silenced the institutional role played by the school where the book was displayed for eighty years.