Regarding its swift happening, why should it not be mine?

This couplet expresses a deep sense of hopeful anticipation. It's like asking, "Why shouldn't this good thing that's about to happen, happen to me?" It reflects a spirit of optimism, where one feels they are deserving of a positive outcome, especially if it's on its way soon. It's a natural human feeling of desiring good fortune and wondering why it shouldn't be yours. This captures the eagerness for a positive future and a personal claim on upcoming happiness, suggesting a belief in one's own deservingness.