Ephesians 3:16-21: "16 that according to the riches of his glory he may grant you to be strengthened with power through his Spirit in your inner being, 17 so that Christ may dwell in your hearts through faith - that you, being rooted and grounded in love, 18 may have strength to comprehend with all the saints what is the breadth and length and height and depth, 19 and to know the love of Christ that surpasses knowledge, that you may be filled with all the fullness of God.
"20 Now to him who is able to do far more abundantly than all that we ask or think, according to the power at work within us, 21 to him be glory in the church and in Christ Jesus throughout all generations, forever and ever. Amen."
Galatians 2:20: "I have been crucified with Christ. It is no longer I who live, but Christ who lives in me. And the life I now live in the flesh I live by faith in the Son of God, who loved me and gave himself for me."
1 John 3:24: "Whoever keeps his commandments abides in God, and God in him. And by this we know that he abides in us, by the Spirit whom he has given us."
John 15:9: "'As the Father has loved me, so have I loved you. Abide in my love.'"
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The text is public domain:
Jesus, Thy boundless love to meNo thought can reach, no tongue declare;Unite my thankful heart to Thee,And reign without a rival there!Thine wholly, Thine alone I am;Be Thou alone my constant flame.O grant that nothing in my soulMay dwell, but Thy pure love alone;Oh, may Thy love possess me whole,My joy, my treasure, and my crown!All coldness from my heart remove;My ev'ry act, word, thought be love.This love unwearied I pursueAnd dauntlessly to Thee aspire.Oh, may Thy love my hope renew,Burn in my soul like heav'nly fire!And day and night, be all my careTo guard this sacred treasure there.In suff'ring by Thy love my peace,In weakness by Thy love my pow'r;And when the storms of life shall cease,O Jesus, in that final hour,Be Thou my rod and staff and guide,And draw me safely to Thy side!
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The text from Ephesians 3 appears at the beginning of the first verse: "Jesus, Thy boundless love to me / No thought can reach, no tongue declare; / Unite my thankful heart to Thee, / And reign without a rival there!"
Along with Galatians 2:20 and 1 John 3:24, the text from Ephesians 3 (specifically verse 17) also appears at the beginning of the second verse: "O[h] grant that nothing in my soul / May dwell, but Thy pure love alone."
John 15:9 seems to appear at the end of the second verse and the beginning of the third: "My ev'ry act, word, thought be love. // This love unwearied I pursue / And dauntlessly to Thee aspire."
The line "Be Thou my rod and staff and guide" in the fourth verse alludes to the end of Psalm 23:4: "your rod and your staff, they comfort me."
"Day and night" in the third verse is a temporal merism.