For the Son of Man has come to save that which was lost. (Matthew 18:11)
A prayer from the ancient Syriac Christian tradition for those who are spiritually lost or who have gone astray:
“I beg and beseech You, Lord,
grant to all who have gone astray
a true knowledge of you,
so that each and every one
may come to know your glory.
In the case of all who have passed from this world
lacking a virtuous life and having had no faith,
be an advocate for them, Lord,
for the sake of the body which you took from them,
so that from the single united body of the world
we may offer up praise
to Father, Son, and Holy Spirit
in the kingdom of heaven,
an unending source of eternal delight.”
(The Syriac Fathers on Prayer and the Spiritual Life, pg. 354)