Ephesians 2:1: "And you were dead in the trespasses and sins"
Ephesians 2:4-9: "4 But God, being rich in mercy, because of the great love with which he loved us, 5 even when we were dead in our trespasses, made us alive together with Christ - by grace you have been saved - 6 and raised us up with him and seated us with him in the heavenly places in Christ Jesus, 7 so that in the coming ages he might show the immeasurable riches of his grace in kindness toward us in Christ Jesus. 8 For by grace you have been saved through faith. And this is not your own doing; it is the gift of God, 9 not a result of works, so that no one may boast."
John 1:14: "And the Word became flesh and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth."
John 1:16-17: "16 And from his fullness we have all received, grace upon grace. 17 For the law was given through Moses; grace and truth came through Jesus Christ."
Hebrews 4:16: "Let us then with confidence draw near to the throne of grace, that we may receive mercy and find grace to help in time of need."
Romans 3:22b-24: "For there is no distinction: 23 for all have sinned and fall short of the glory of God, 24 and are justified by his grace as a gift, through the redemption that is in Christ Jesus"
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The text is public domain:
1 Amazing grace - how sweet the sound -That saved a wretch like me!I once was lost but now am found,Was blind but now I see!2 The Lord has promised good to me,His Word my hope secures;He will my shield and portion beAs long as life endures.3 Through many dangers, toils, and snaresI have already come;His grace has brought me safe thus far,His grace will lead me home.4 Yes, when this flesh and heart shall failAnd mortal life shall cease,Amazing grace shall then prevailIn heaven's joy and peace.5 When we've been there ten thousand years,Bright shining as the sun,We've no less days to sing God's praiseThan when we'd first begun.
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The two passages from Ephesians (particularly Ephesians 2:5) appear in the first two lines: "Amazing grace - how sweet the sound - / That saved a wretch like me!" Aside from Ephesians 2:1, all of the citations mention grace, which appears in the title line and in the third and fourth verses.
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The second half of the first verse ("I once was lost but now am found, / Was blind but now I see!") borrows phrases from the Parable of the Lost Son (Luke 15:24: "'"For this my son was dead, and is alive again; he was lost, and is found." And they began to celebrate.'") and from the account of the man born blind (John 9:25: "He answered, 'Whether he is a sinner I do not know. One thing I do know, that though I was blind, now I see.'").
The descriptions of God as "shield" and "portion" in the second verse also occur in various Psalms, including 3:3; 28:7; 33:20; 73:26; 84:11; 119:57 and 142:5.
The line "Bright shining as the sun" in the fifth verse is drawn from Matthew 13:43: "'Then the righteous will shine like the sun in the kingdom of their Father. He who has ears, let him hear.'"