Tiwaz (ᛏ), seventeenth rune and first of Tyr's ætt, bears the name of Týr himself — the one-handed god of law, justice, and the thing-assembly. In the Prose Edda (Gylfaginning ch. 25), Týr places his hand in the mouth of the Fenris-wolf as a pledge of good faith while the other Æsir bind the beast with Gleipnir; when Fenrir discovers the trick, he bites off Týr's hand. The upward-pointing arrow of the Tiwaz stave was carved on sword-blades to invoke victory, as the Sigrdrifumál (stanza 6) instructs: 'Victory-runes you must cut if you want to have victory, and carve them on your sword-hilt.' Tiwaz governs the principle that cosmic order (ON: réttr) demands personal sacrifice — the law holds only because someone is willing to lose something in its enforcement.