Final means "end" or "finale." While it might seem like a common word, its usage in this song, particularly in the title "Hasta Mi Final," gives it a profound and romantic weight.
Il Divo sings about loving "hasta mi final" (until my end), signifying an eternal and unwavering commitment. It's a powerful declaration of lifelong devotion, making this seemingly simple word deeply meaningful in the context of the song's theme of everlasting love.
Il Divo built "Hasta mi final" as a straightforward marriage vow set to music. It opens with the singer placing his partner beside him for good: "Tu lugar es a mi lado, hasta que lo quiera Dios" (Your place is by my side, until God wills it). He is not describing a feeling so much as making a legal-sounding promise — he has never been "tan seguro" (so sure) of anything, and he says so plainly: "Nunca estuve tan seguro de amar así, sin condición" (I have never been so sure of loving this way, unconditionally).
The chorus repeats like actual vows exchanged at an altar: "Hoy te prometo amor eterno, ser para siempre tuyo en el bien y en el mal" (Today I promise you eternal love, to be forever yours in good and in bad) — the Spanish even borrows the wedding-ceremony phrase "en el bien y en el mal." It closes on the title line repeated as a refrain, "amándote hasta mi final" (loving you until my end), turning the whole song into one long answer to a single question: how long will this last.