Isaiah 12:2: "'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.'"
Matthew 28:18-20: "18 And Jesus came and said to them, 'All authority in heaven and on earth has been given to me, 19 Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, 20 teaching them to observe all that I have commanded you. And behold, I am with you always, to the end of the age.'"
Isaiah 26:3: "You keep him in perfect peace whose mind is stayed on you, because he trusts in you."
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The text is public domain:
1 I am trusting Thee, Lord Jesus,Trusting only Thee;Trusting Thee for full salvation,Great and free.2 I am trusting Thee for pardon;At Thy feet I bow,For Thy grace and tender mercyTrusting now.3 I am trusting Thee for cleansingIn the crimson flood;Trusting Thee to make me holyBy Thy blood.4 I am trusting Thee to guide me;Thou alone shalt lead,Ev'ry day and hour supplyingAll my need.5 I am trusting Thee for power;Thine can never fail.Words which Thou Thyself shalt give meMust prevail.6 I am trusting Thee, Lord Jesus;Never let me fall.I am trusting Thee foreverAnd for all.
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The two verses from Isaiah appear in "I am trusting Thee," which begins every verse. Parts of Isaiah 12:2 also appear elsewhere: "God is my salvation" in the line "Trusting Thee for full salvation" in the first verse and "the LORD GOD is my strength" in the line "I am trusting Thee for power" in the fifth.
"'All authority in heaven and on earth has been given to me'" from the Matthew 28 passage overlaps a bit with Isaiah 12:2 in the line "I am trusting Thee for power," and "'And behold, I am with you always, to the end of the age'" seems to be referred to in the lines "Words which Thou Thyself shalt give me" in the fifth verse and "I am trusting Thee forever" in the sixth (with the "forever" echoing Jesus' "'always'").