All tragedies are finish'd by a death,
All comedies are ended by a marriage;
The future states of both are left to faith.
. . .

The lines from Byron's "Don Juan" cleverly juxtapose the traditional endings of tragedies and comedies, using them as metaphors for the unpredictability of life. Tragedies, with their inevitable deaths, contrast with comedies, which traditionally culminate in marriage. Yet, the future of both scenarios is left uncertain, handed over to "faith." Byron's commentary extends beyond literary convention to a critique of marriage itself, shaped by his own disillusionment with his marriage to Anne Isabella Milbanke. This coupling of comedy with marriage suggests that, while marriage may seem a happy ending, it also marks the beginning of an unknowable future. Byron implies that, like in tragedy, the outcomes of marriage are uncertain and vulnerable to human frailty and folly. Thus, the quote challenges the notion of marriage as a definitive conclusion, underscoring the unpredictable nature of human relationships.