Lord Jesus Christ,
true God and truly human,
you do not change,
and you are holy in all your works.
Remove all our unbelief and doubt,
and fill our hearts with the gifts of your grace
that we may believe and know you as true God,
and by your miracles and mighty works
know you as Savior of all.
Source: Mozarabic, freely modified from Ancient Collects, ed. William Bright, p. 75.4. Also in Mozarabic Collects, ed. Rev. Chas. R. Hale, New York, 1881, p. 27 #3 (Easter 4)
“true God and fully human” is a reference to 1 Timothy 2:5
“you do not change” is a reference to Malachi 3:6, Hebrews 13:8
“Remove all our unbelief and doubt” is a reference to Mark 9:24
Born as a Son,
led forth as a lamb,
sacrificed as a sheep,
buried as a man,
he rose from the dead as a God,
for he was by nature God and man.
He is all things:
he judges, and so he is law;
he teaches, and so he is wisdom;
he saves, and so he is grace;
he is begotten, and so he is Son;
he suffers, and so he is sacrifice;
he is buried, and so he is man;
he rises again, and so he is God.
This is Jesus Christ,
to whom belongs glory for all ages.
Source: Melito of Sardis, d. 189
Modified from http://www.catholicdoors.com/prayers/english/p00395.htm
A line was omitted after “he saves, and so he is grace” because of possible doctrinal confusion.