John 11:25-26: "25 Jesus said to her, 'I am the resurrection and the life. Whoever believes in me, though he die, yet shall he live, 26 and everyone who lives and believes in me shall never die. Do you believe this?'"
Romans 6:4-11: "4 We were buried therefore with him by baptism into death, in order that, just as Christ was raised from the dead by the glory of the Father, we too might walk in newness of life.
"5 For if we have been united with him in a death like his, we shall certainly be united with him in a resurrection like his. 6 We know that our old self was crucified with him in order that the body of sin might be brought to nothing, so that we would no longer be enslaved to sin. 7 For one who has died has been set free from sin. 8 Now if we have died with Christ, we believe that we will also live with him. 9 We know that Christ, being raised from the dead, will never die again; death no longer has dominion over him. 10 For the death he died he died to sin, once for all, but the life he lives he lives to God. 11 So you also must consider yourselves dead to sin and alive to God in Christ Jesus."
Romans 8:1-4: "1 There is therefore now no condemnation for those who are in Christ Jesus. 2 For the law of the Spirit of life has set you free in Christ Jesus from the law of sin and death. 3 For God has done what the law, weakened by the flesh, could not do. By sending his own Son in the likeness of sinful flesh and for sin, he condemned sin in the flesh, 4 in order that the righteous requirement of the law might be fulfilled in us, who walk not according to the flesh but according to the Spirit."
1 Corinthians 15:55-57: "55 'O death, where is your victory? O death, where is your sting?' 56 The sting of death is sin, and the power of sin is the law. 57 But thanks be to God, who gives us the victory through our Lord Jesus Christ."
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The text is public domain:
I am content! My Jesus ever lives,
In whom my heart is pleased.
He has fulfilled the Law of God for me,
God's wrath He has appeased.
Since He in death could perish never,
I also shall not die forever.
I am content!
I am content!
I am content! My Jesus is my head;
His member I shall be.
He bowed His head when on the cross He died
With cries of agony.
Now death is brought into subjection
For me by Jesus' resurrection.
I am content!
I am content!
I am content! My Jesus is my light,
My radiant sun of grace.
His cheering rays beam blessings forth for all,
Sweet comfort, hope, and peace.
This Easter sun has brought salvation
And everlasting exultation.
I am content!
I am content!
I am content! At length I shall be free,
Awakened from the dead,
Arising glorious evermore to be
With You, my living head.
The chains that hold my body, sever;
Then shall my soul rejoice forever.
I am content!
I am content!
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The first three citations all seem to appear in the first verse, specifically in the lines "He has fulfilled the Law of God for me, / God's wrath He has appeased. / Since He in death could perish never, / I also shall not die forever." The being set free that's mentioned in both texts from Romans appears in the last verse, in the lines "I am content! At length I shall be free" and "The chains that hold my body, sever; / Then shall my soul rejoice forever."
The verses from 1 Corinthians 15 appear in the line "Now death is brought into subjection" in the second verse.
"My Jesus is my head" in the second verse and "With You, my living head" in the fourth both seem to come from Colossians 1:18: "And he is the head of the body, the church. He is the beginning, the firstborn from the dead, that in everything he might be preeminent."
"His member I shall be" in the second verse seems to refer to the second half of 1 Corinthians 12, beginning with verse 12: "For just as the body is one and has many members, and all the members of the body, though many, are one body, so it is with Christ."