“With many references to original sources in the seventeenth century, he shows that the Presbyterian concept of the covenant of grace relies upon a substance/administration hermeneutic which leads to the “one covenant under two administrations (OT/NT)” structure. This structure allows the Presbyterian to transfer the organic element of “believers and their seed” from the Abrahamic/Sinai Covenant administration into the new covenant administration, thus allowing a mixed church of believers and unbelievers as well as infant”