Matthew 26:26-29: "26 Now as they were eating, Jesus took bread, and after blessing it broke it and gave it to the disciples, and said, 'Take, eat; this is my body.' 27 And he took a cup, and when he had given thanks he gave it to them, saying, 'Drink of it, all of you, 28 for this is my blood of the covenant, which is poured out for many for the forgiveness of sins. 29 I tell you I will not drink again of this fruit of the vine until that day when I drink it new with you in my Father's kingdom.'"
Hebrews 7:23-27: "23 The former priests were many in number, because they were prevented by death from continuing in office, 24 but he holds his priesthood permanently, because he continues forever. 25 Consequently, he is able to save to the uttermost those who draw near to God through him, since he always lives to make intercession for them.
"26 For it was indeed fitting that we should have such a high priest, holy, innocent, unstained, separated from sinners, and exalted above the heavens. 27 He has no need, like those high priests, to offer sacrifices daily, first for his own sins and then for those of the people, since he did this once for all when he offered up himself."
1 Peter 1:18-19: "18 knowing that you were ransomed from the futile ways inherited from your forefathers, not with perishable things such as silver or gold, 19 but with the precious blood of Christ, like that of a lamb without blemish or spot."
Revelation 7:13-17: "13 Then one of the elders addressed me, saying, 'Who are these, clothed in white robes, and from where have they come?' 14 I said to him, 'Sir, you know.' And he said to me, 'These are the ones coming out of the great tribulation. They have washed their robes and made them white in the blood of the Lamb.
"15 'Therefore they are before the throne of God, and serve him day and night in his temple; and he who sits on the throne will shelter them with his presence. 16 They shall hunger no more, neither thirst anymore; the sun shall not strike them, nor any scorching heat. 17 For the Lamb in the midst of the throne will be their shepherd, and he will guide them to springs of living water, and God will wipe away every tear from their eyes.'"
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The passage from Matthew 26 is the main basis of the hymn, and roughly the first four verses are drawn from it.
The passage from Hebrews 7 appears in the second verse: "Christ Himself, the priest presiding...."
1 Peter 1:18-19 appears in the second half of the third verse: "Blood and body, giv'n for me, / Very Lamb of God from heaven, / Who to bitter death was given, / Hung upon the cursed tree."
The white robes from Revelation 7:13-14 are referred to in the fifth verse: "Wedding garments He provides me, / With a robe of white He hides me, / Fits me for the royal hall." The rest of the passage from Revelation 7 appears in the sixth verse. The line "God, my shield from ev'ry terror" may also draw from Psalm 91:4-5, which uses similar language: "4 He will cover you with his pinions, and under his wings you will find refuge; his faithfulness is a shield and buckler. 5 You will not fear the terror of the night, nor the arrow that flies by day."