Tertullian The Prescription Against Heretics of all the rest, but because "by three witnesses must every word be established."[233] Tertullian Against Marcion Book IV ."[1690] Tertullian Against Marcion Book V still retains the very formula of the law: "In the mouth of two or three witnesses shall every word be established? "[591] Tertullian On Baptism three witnesses every word shall stand: "[47]