The Nahel bond is a symbiotic bond between humans and certain types of spren.
It is a mutually beneficent relationship that gives the spren a stronger presence in the Physical Realm and the ability to think and remember more clearly in that Realm. Presumably, it also grants the person bound to the spren a stronger presence in the Cognitive Realm, allowing her/him to manipulate Stormlight more potently, as does Lift.
The Nahel bond has been known of since the Heraldic Epochs.
|“||They also, when they had settled their rulings in the nature of each bond’s placement, called the name of it the Nahel bond, with regard to its effect upon the souls of those caught in its grip; in this description, each was related to the bonds that drive Roshar itself, ten Surges, named in turn and two for each order; in this light, it can be seen that each order would by necessity share one Surge with each of its neighbor.||”|
More recently, Sylphrena bonded with Kaladin, who awakens as a Windrunner. Kaladin was made stronger after saying the First Ideal of the Knights Radiant, though Syl was attracted to him long before this occurred. He was further strengthened after saying the Second and Third Ideals.
Szeth has no spren, yet can make use of Surges. This horrifies Syl because his Surges do not come from Honor, as do those of the Radiants. Conversely, his ability to Surgebind come from his wielding an Honorblade, and then from being a squire of the Herald of Justice and Skybreaker, Nale.
Shallan bonded a Cryptic when she was quite young, which more recently was influential in awakening her as a Lightweaver and becoming a Shardblade when she kills, and when she unlocks the Oathgate. By the end of Words of Radiance, she has spoken the First Ideal and must now speak only truths.
Jasnah bonded with Ivory, though at just what time this occurred remains unknown. Jasnah has already proved that her Surgebinding abilities are her own, and not the result of her Soulcasting abilities with her Soulcasting device.
|“||"Alakavish was a Surgebinder. He should have known better. And yet, the Nahel bond gave him no more wisdom than a regular man. Alas, not all spren are as discerning as honorspren."||”|
|“||"They need to be better, old friend. We all do. The responsibility of what we've been given - whether it be the crown or the Nahel bond - needs to make us better."||”|
–Nohadon, in Dalinar's visions
According to Syl, spren normally weather the death of their Radiant.
- Syl and the Nahel bond
- Words of Radiance, Inter9.
- Oathbringer, 108. Honor's Path
- Dragonsteel Mini-Con 2021, 11/22/21
- Words of Radiance, 35. The Multiplied Strain Of Simultaneous Infusion
- The Way of Kings, 60. That Which We Cannot Have
- The Way of Kings, 59. An Honor
- The Way of Kings, 2. Honor is Dead
- The Way of Kings, 67. Words
- Words of Radiance, 84. The One Who Saves
- Oathbringer, 90. Reborn
- Words of Radiance, 10. Red Carpet Once White
- Words of Radiance, 34. Blossoms And Cake
- Words of Radiance, 86. Patterns Of Light
- Words of Radiance, 17. A Pattern
- Words of Radiance, 87. The Riddens
- Words of Radiance, Prologue - To Question
- The Way of Kings, 48. Strawberry
- Words of Radiance, 89. The Four
- Oathbringer, 116. Alone
- Oathbringer, Epilogue - Great Art
- Awakened and the Nahel bond
- Oathbringer, 95. Inescapable Void