This is a worship song, and Alex Zurdo, the Puerto Rican Christian rapper, spends the whole thing asking one question he cannot answer: "Jesús, ¿por qué me amas tanto?" (Jesus, why do you love me so much?). He is not bragging about his faith. He is listing the ways he has let Jesus down and then being stunned that the love keeps coming back anyway.
The chorus is the clearest example. "¿Por qué me abrazas cuando te fallé?" (Why do you hug me when I failed you?) and "Y me abrigas con tu manto" (And you wrap me in your cloak). Abrigar is a lovely verb to learn here: it means to wrap someone up to keep them warm, the way you would with a coat (un abrigo).
The rap verse is where Zurdo shows off, stacking rhymes on -illa: rodillas, silla, rencilla, milla, mejilla, semilla, bombilla. He confesses he did not walk the extra mile ("no andar mi otra milla") or turn the other cheek ("no poner mi otra mejilla"), both straight from the Gospels. Then comes the strongest image in the song: "Quitaste mi nombre y pusiste el tuyo en la sentencia" (You took my name off and put yours on the sentence), a picture of Jesus taking his punishment.
It ends small, with one word on its own line: "Gracias" (Thank you), "por amarme tanto" (for loving me so much).