Then why are you mixing poison? It is just to fulfill my promise.

This couplet speaks about creating a tough situation, almost like mixing poison, but not literally. It's about someone putting immense pressure or creating a challenging circumstance. The reason behind this drastic action is to ensure that a promise made to them is absolutely fulfilled. It highlights how sometimes people go to extreme lengths, metaphorically speaking, to hold others accountable to their word and commitment. It's a powerful way to convey the seriousness of ensuring promises are kept, even if it means making things difficult.