Celos translates to "jealousy." While it's a common emotion, its prominent placement in the lyrics, "Sombra de duda y celos, Todo me envuelve pensando en ti," makes it particularly impactful in this song.
It's not just a fleeting feeling, but a "shadow of doubt and jealousy" that completely envelops the singer, highlighting the intensity of his emotional turmoil and regret over a lost love. This word captures a core theme of the song's heartbreak and longing.
Vicente Fernández's "Cielo Rojo" is a classic ranchera about a man lost in regret and longing after a breakup. He's walking alone, asking the sky for answers about his lost love, but even the sky is silent: "Ni el cielo me contesta cuando pregunto por ti, mujer" [Not even the sky answers me when I ask about you, woman]. He admits he hasn't been able to forget her since the night he lost her, and now he's consumed by "Sombra de duda y celos" [Shadows of doubt and jealousy] whenever he thinks of her.
He's desperate for a second chance, pleading with her to forget the past and come back: "Olvida lo pasado, ya no te acuerdes de aquel ayer" [Forget the past, don't remember that yesterday]. He dreams of them together under a blue sky, but when he wakes up, his reality is a "cielo es rojo, le faltas tú" [sky is red, you are missing]. He even takes responsibility for their separation, saying "Aunque yo sea culpable de aquella triste... separación" [Even though I am guilty of that sad... separation], and begs her to return to him. It's a powerful song about wanting to fix what's broken and get back the love he lost.