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.'"
1 Corinthians 11:27-29: "27 Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty concerning the body and blood of the Lord. 28 Let a person examine himself, then, and so eat of the bread and drink of the cup. 29 For anyone who eats and drinks without discerning the body eats and drinks judgement on himself."
1 Corinthians 10:16: "The cup of blessing that we bless, is it not a participation in the blood of Christ? The bread that we break, is it not a participation in the body of Christ?"
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."
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The text is public domain:
The death of Jesus Christ, our Lord,We celebrate with one accord;It is our comfort in distress,Our heart's sweet joy and happiness.
He blotted out with His own bloodThe judgement that against us stood;For us He full atonement made,And all our debt He fully paid.
That this forever true shall beHe gives a solemn guarantee:In this His holy Supper hereWe taste His love so sweet, so near.
His Word proclaims and we believeThat in this Supper we receiveHis very body, as He said,His very blood for sinners shed.
We dare not ask how this can be,But simply hold the mysteryAnd trust this word where life begins:"Give and shed for all your sins."
They who this word do not believeThis food unworthily receive,Salvation here will never find -May we this warning keep in mind!
But blest is each believing guestWho in these promises finds rest;For Jesus shall in love remainWith all who here His grace obtain.
Help us sincerely to believeThat we may worthily receiveYour Supper and in You find rest.Amen! They who believe are blest.
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The passages from Matthew 26:26-29 and 1 Corinthians 10:16 are the main sources for the hymn and are referred to in most of the verses. 1 Corinthians 11:27-29 appears in the sixth and eighth verses, and Peter 1:18-19 appears in the second.