Summary
Frodo and Sam are stuck in the Emyn Muil, with no food but lembas and no way to get into Mordor. They go down into a gully whose bottom is a cliff. Frodo climbs down and then falls when a Black Rider passes over. Sam remembers the elven rope he was given and hauls him back up. Finally they use the rope to climb down, and the rope obediently unties itself afterward. While resting a little farther on, they spot Gollum behind them climbing face down the cliff. He ends up falling and Sam pounces on him, but Frodo gives him the choice of guiding them instead. He agrees, but tries to escape at the first opportunity. Frodo has Sam tie him up, but the elven rope hurts Smeagol, so Frodo forces him to swear by the Ring "to be very, very good" and "never to let Him have it." His actual promise is "to serve the master of the Precious." Frodo accepts and has Sam remove the rope. Smeagol tells them he knows a way across the marshes.
Questions
1. What exactly about the rope is hurting Smeagol? Is it physical or psychological?
2. Smeagol's promise is actually very vague. Why does Frodo let him get away with it?