The Canticle “I Will Give Thanks” (Confiteor Tibi) is taken from Isaiah 12:1-6. In the 1979 Book of Common Prayer it was called The First Song of Isaiah, Ecce Deus.
I will give thanks to you, O LORD, for though you were angry with me,
your anger turned away, that you might comfort me.
Behold, God is my salvation;
I will trust, and will not be afraid;
for the LORD GOD is my strength and my song,
and he has become my salvation.
With joy you will draw water
from the wells of salvation.
And you will say in that day:
Give thanks to the LORD, call upon his name,
make known his deeds among the peoples,
proclaim that his name is exalted.
Sing praises to the LORD, for he has done gloriously;
let this be made known in all the earth.
Shout, and sing for joy, O inhabitant of Zion,
for great in your midst is the Holy One of Israel.
Glory be to the Father, and to the Son, and to the Holy Spirit:
as it was in the beginning, is now, and will be forever. Amen.
Source: Holy Bible: English Standard Version.
The text of this canticle has been given a contemporary setting. The text is the translation in the 1979 Book of Common Prayer.
Text from the 1979 U. S. Book of Common Prayer (Episcopal) in Daily Morning Prayer, Rite Two.
9 The First Song of Isaiah Ecce, Deus
Surely, it is God who saves me; *
I will trust in him and not be afraid.
For the Lord is my stronghold and my sure defense, *
and he will be my Savior.
Therefore you shall draw water with rejoicing *
from the springs of salvation.
And on that day you shall say, *
Give thanks to the Lord and call upon his Name;
Make his deeds known among the peoples; *
see that they remember that his Name is exalted.
Sing the praises of the Lord, for he has done great things, *
and this is known in all the world.
Cry aloud, inhabitants of Zion, ring out your joy, *
for the great one in the midst of you is the Holy One of Israel.
Glory to the Father, and to the Son, and to the Holy Spirit: *
as it was in the beginning, is now, and will be for ever. Amen.
Source: 1979 U.S. Book of Common Prayer.