Bautizamos literally means "we baptized." While often associated with religious ceremonies, in this song, it's used metaphorically in a very poetic and unique way.
Antonio José sings, "De cuando bautizamos en el mar / Aquel amor de locos que nos pedía arena" (From when we baptized in the sea / That crazy love that asked for sand). Here, "bautizamos" signifies a profound, almost sacred, initiation or consecration of their passionate love in the vastness of the sea, making it a memorable and evocative word choice.
Antonio José opens “La Noche Encendida” already in memory. “He guardado en una caja de cristal” [I've kept in a crystal box], “Algún recuerdo nuestro y tres o cuatro piedras” [Some memory of ours and three or four stones], saved from “De cuando bautizamos en el mar” [When we baptized in the sea], a love the two of them built themselves: “Nos inventamos lo demás” [We made up the rest].
The chorus turns that memory into a standing invitation: “Tengo la noche encendida un beso y la luna en la ventana” [I have the night lit a kiss and the moon in the window], kept ready “Por si vuelves a mis sueños” [In case you come back to my dreams]. He doesn't pretend the odds are good. “Aunque sé muy bien que no te tengo amor” [Although I know very well that I don't have you, love] gives way to the title's real trick, a line that argues with itself: “Te tengo amor, no te tengo amor” [I have you, love, I don't have you, love].