John 14:23: "Jesus answered him, 'If anyone loves me, he will keep my word, and my Father will love him, and we will come to him and make our home with him.'"
1 John 4:19: "We love because he first loved us."
John 8:12: "Again Jesus spoke to them, saying, 'I am the light of the world. Whoever follows me will not walk in darkness, but will have the light of life.'"
+++
The text is public domain:
Thee will I love, my strength, my tower;Thee will I love, my hope, my joy.Thee will I love with all my power,With ardor time shall ne'er destroy.Thee will I love, O Light divine,So long as life is mine.Thee will I love, my life, my Savior,Who art my best and truest friend.Thee will I love and praise forever,For never shall Thy kindness end.Thee will I love with all my heart -Thou my Redeemer art!I thank Thee, Jesus, Sun from heaven,Whose radiance hath brought light to me;I thank Thee, who has richly givenAll that could make me glad and free;I thank Thee that my soul is healedBy what Thy lips revealed.O keep me watchful, then, and humble;Permit me nevermore to stray.Uphold me when my feet would stumble,And keep me on the narrow way.Fill all my nature with Thy light,O Radiance strong and bright!Thee will I love, my crown of gladness;Thee will I love, my God and Lord,Amid the darkest depths of sadness,And not for hope of high reward,For Thine own sake, O Light divine,So long as life is mine.
+++
John 14:23 and 1 John 4:19 both seem to appear throughout the hymn ("Thee will I love") but more generally than specifically.
John 8:12 (particularly "'I am the light of the world'") seems to be referred to in a few places: the phrase "O Light divine" in the first and fifth verses, the lines "I thank Thee, Jesus, Sun from heaven, / Whose radiance hath brought light to me" in the third verse, and the line "Fill all my nature with Thy light" in the fourth verse.
The description of God as "my tower" in the first verse may come from Psalm 61:3: "for you have been my refuge, a strong tower against the enemy."
