This is a pseudepigraphical Testament — a deathbed speech attributed to the biblical patriarch Dan, son of Jacob — drawn from *The Testaments of the Twelve Patriarchs*, a Jewish apocryphal text presented in the 1926 Platt collection *The Forgotten Books of Eden*. Dan confesses that jealousy over his father's favoritism toward Joseph drove him to plot Joseph's murder, and he frames this personal failure as the occasion for a moral teaching to his sons. The core argument is that anger is a form of spiritual blindness: it distorts perception so thoroughly that an enraged person cannot recognize family, friend, prophet, or righteous man, and instead sees all as enemies. A notably specific psychological claim is that anger "giveth its own peculiar vision" — a warped inner sight produced by hatred — which corrupts not just behavior but the soul's capacity to judge its own actions as wrong. Dan also maps anger's social amplification, arguing that a wrathful man leverages wealth, servants, and physical strength to multiply his destructive power, while even a weak man's anger doubles his effective capacity for lawlessness. The text closes with practical counsel against both provocation and flattery as triggers, positioning anger and lying as twin instruments of Beliar (Satan) that, left unchecked, drive the Lord from the soul entirely.