Left arm — Gevurah
Arm of severity (anatomical left per landmark convention)
The left arm of Adam Kadmon, identified with the sefirah of Gevurah (גבורה, 'severity' / 'might'), also called Din ('judgement'). Gevurah is the left-side restraining and limiting principle: the necessary judgement that gives form to mercy, the strength that says 'no' so that the right hand's 'yes' can mean anything. The Patriarch Isaac (the human exemplar of Gevurah, exemplified by his binding at Moriah) is the figure of the left-arm sefirah. Following this project's coordinate convention, anatomical-left is at x>0.5 on the front-view silhouette; we render the rendered point at the left-shoulder / clavicle landmark (x=0.645, y=0.215). The right-arm Chesed and left-arm Gevurah pair is the Idrot's most famous Kabbalistic body-image: the two arms that meet in the heart of Tiferet, where mercy and judgement are reconciled.
Point 4 of 5 in Adam Kadmon — Cosmic-Body Mapping (Lurianic)
Cross-tradition overlaps
No overlapping points are registered for this point.
Sources
Zohar — Idra Rabba Naso 142a–143b (primary_canonical)
“His left arm is the arm of severity. From it issues the fire of judgement.”
Chayyim Vital, Etz Chaim, Sha'ar HaSefirot (primary_canonical)
Sha'ar HaSefirot presents Gevurah as the left-side, limiting and judging sefirah paired with Chesed, which is the textual basis for the left-arm correspondence. Gate sub-section numbering varies among printings of Etz Chaim.