Riu Riu Chiu; my favorite Christmas carol this season

Riu, riu, chiu
La guarda rivera
Dios guarda el lobo
De nuestra cordera

Riu, riu, chiu

El lobo rabioso la quiso morder
Mas Dios poderoso la supo defender
Quisole hacer que no pudiese pecar
Ni aun original la Virgen no tuviera

Riu, riu, chiu
La guarda rivera

Este viene a dar a los muertos vida
Y viene a reparar de todos la caida
Es la luz del dia aqueste mochuelo
Este es el cordero que San Juan dijera

Riu, riu, chiu
Guarda rivera

Este qu'es nacido es el gran monarca
Cristo patriarca de carne vestido
Hemos redimido con se hacer chiquito
Aunqu'era infinito, finito se hiciera

Riu, riu, chiu
La guarda rivera


English Translation:
Riu, riu, chiu
The river bank protects it,
As God kept the wolf from the lamb.

The rabid wolf tried to bite her,
But God Almightly knew how to defend her,
He wished to create her impervious to sin,
Nor was this maid to embody original sin.

Riu, riu, chiu
The river bank protects it,
As God kept the wolf from the lamb.

He comes to give life to the dead,
He comes to redeem the fall of man;
This Child is the light of day,
He is the very Lamb Saint John prophecied.

Riu, riu, chiu
The river bank protects it,
As God kept the wolf from the lamb.

A thousand singing herons I saw passing,
Flying overhead, sounding a thousand voices,
Exhulting, "Glory be in the heavens, and peace on earth,
For Jesus has been born."

Riu, riu, chiu
The river bank protects it,
As God kept the wolf from the lamb.
Riu, riu, chiu (nightingale's sounds)

Riu, riu, chiu was written in so-called villancico style, which became a popular form for songs in post-Renaissance Spain. Such songs are in ternary form, with a text expressing some aspect of Christian principles or beliefs. This carol became one of the more widely known such works in its time. The author of this carol is generally thought to be anonymous, but its text, possibly originally written in Portuguese, has been attributed by some to Mateo Flecha (1481-1553). The melody to Riu, riu, chiu probably dates to the fifteenth century or earlier. The words in the title are vocalizations of the sounds made by a nightingale. The main theme is lively and rhythmic and has an instant appeal, lingering in the mind long after one or two hearings. It exudes folk-ish color.  One hears a mixture of Renaissance-era elegance here with a sort of peasant-like festivity. Its text speaks of the roles of the Blessed Mother and the Redeemer. ~ All Music Guide