Pope Leo XIII in 1889 suggested that it be added to the end of the Rosary, especially in October.
In this Year of St. Joseph called by Pope Francis, there is an opportunity for a plenary indulgence with the recitation of approved prayers to the saint. The Vatican’s office of indulgences mentioned as one example a prayer that goes back to 1889, and Pope Leo XIII’s encyclical Quamquam pluries.
That pope asked that this prayer be added to the end of the Rosary, especially during the month of October, which is dedicated to the Rosary. If prayed after the Rosary, it could be said after the Salve Regina and concluding prayer.
The US bishops note that it can also be used to conclude other Marian devotions.
Now it’s being highlighted as a devotion that is especially apt for seeking a plenary indulgence on Wednesdays, other days devoted to St. Joseph, or any day during this Holy Year of St. Joseph.
To you, O blessed Joseph,
do we come in our tribulation,
and having implored the help of your most holy Spouse,
we confidently invoke your patronage also.
Through that charity which bound you
to the Immaculate Virgin Mother of God
and through the paternal love
with which you embraced the Child Jesus,
we humbly beg you graciously to regard the inheritance
which Jesus Christ has purchased by his Blood,
and with your power and strength to aid us in our necessities.
O most watchful guardian of the Holy Family,
defend the chosen children of Jesus Christ;
O most loving father, ward off from us
every contagion of error and corrupting influence;
O our most mighty protector, be kind to us
and from heaven assist us in our struggle
with the power of darkness.
As once you rescued the Child Jesus from deadly peril,
so now protect God’s Holy Church
from the snares of the enemy and from all adversity;
shield, too, each one of us by your constant protection,
so that, supported by your example and your aid,
we may be able to live piously, to die in holiness,
and to obtain eternal happiness in heaven.
Pope Leo XIII also wrote a well-known Prayer to St. Michael the Archangel, that says “defend us in battle.” Read about that here: