If you're equating the Eucharist with communion, then no Protestants I know of would say communion is not in scripture. However, what is in question is the purpose of communion. Catholic teaching is that the Eucharist is a means of imparting God's grace. There is nothing in scripture that supports this notion. What is in scripture is the Lord Supper proclaims our Lord Jesus' death and is a memorial until He returns.
1Co 11:25 In the same way also he took the cup, after supper, saying, "This cup is the new covenant in my blood. Do this, as often as you drink it, in remembrance of me."
1Co 11:26 For as often as you eat this bread and drink the cup, you proclaim the Lord's death until he comes.
14 Other boats came from Tiberias near the place where they had eaten the bread when the Lord gave thanks. 24 When the crowd saw that neither Jesus nor his disciples were there, they themselves got into boats and came to Capernaum looking for Jesus. 25 And when they found him across the sea they said to him, "Rabbi, when did you get here?" 26 Jesus answered them and said, "Amen, amen, I say to you, you are looking for me not because you saw signs but because you ate the loaves and were filled. 27 Do not work for food that perishes but for the food that endures for eternal life, 15 which the Son of Man will give you. For on him the Father, God, has set his seal." 28 So they said to him, "What can we do to accomplish the works of God?" 29 Jesus answered and said to them, "This is the work of God, that you believe in the one he sent."
30 So they said to him, "What sign can you do, that we may see and believe in you? What can you do? 31 16 Our ancestors ate manna in the desert, as it is written: 'He gave them bread from heaven to eat.'" 32 So Jesus said to them, "Amen, amen, I say to you, it was not Moses who gave the bread from heaven; my Father gives you the true bread from heaven. 33 For the bread of God is that which comes down from heaven and gives life to the world." 34 So they said to him, "Sir, give us this bread always." 35 17 Jesus said to them, "I am the bread of life; whoever comes to me will never hunger, and whoever believes in me will never thirst. 36 But I told you that although you have seen (me), you do not believe. 37 Everything that the Father gives me will come to me, and I will not reject anyone who comes to me, 38 because I came down from heaven not to do my own will but the will of the one who sent me. 39 And this is the will of the one who sent me, that I should not lose anything of what he gave me, but that I should raise it (on) the last day.
40 For this is the will of my Father, that everyone who sees the Son and believes in him may have eternal life, and I shall raise him (on) the last day." 41 The Jews murmured about him because he said, "I am the bread that came down from heaven," 42 and they said, "Is this not Jesus, the son of Joseph? Do we not know his father and mother? Then how can he say, 'I have come down from heaven'?" 43 Jesus answered and said to them, "Stop murmuring 18 among yourselves. 44 No one can come to me unless the Father who sent me draw him, and I will raise him on the last day. 45 It is written in the prophets: 'They shall all be taught by God.' Everyone who listens to my Father and learns from him comes to me. 46 Not that anyone has seen the Father except the one who is from God; he has seen the Father. 47 Amen, amen, I say to you, whoever believes has eternal life.
48 I am the bread of life. 49 Your ancestors ate the manna in the desert, but they died; 50 this is the bread that comes down from heaven so that one may eat it and not die. 51 I am the living bread that came down from heaven; whoever eats this bread will live forever; and the bread that I will give is my flesh for the life of the world." 52 The Jews quarreled among themselves, saying, "How can this man give us (his) flesh to eat?" 53 Jesus said to them, "Amen, amen, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you do not have life within you. 54 Whoever eats 19 my flesh and drinks my blood has eternal life, and I will raise him on the last day. 55 For my flesh is true food, and my blood is true drink. 56 Whoever eats my flesh and drinks my blood remains in me and I in him. 57 Just as the living Father sent me and I have life because of the Father, so also the one who feeds on me will have life because of me. 58 This is the bread that came down from heaven. Unlike your ancestors who ate and still died, whoever eats this bread will live forever."
59 These things he said while teaching in the synagogue in Capernaum. 60 20 Then many of his disciples who were listening said, "This saying is hard; who can accept it?" 61 Since Jesus knew that his disciples were murmuring about this, he said to them, "Does this shock you? 62 What if you were to see the Son of Man ascending to where he was before? 21 63 It is the spirit that gives life, while the flesh 22 is of no avail. The words I have spoken to you are spirit and life. 64 But there are some of you who do not believe." Jesus knew from the beginning the ones who would not believe and the one who would betray him. 65 And he said, "For this reason I have told you that no one can come to me unless it is granted him by my Father." 66 As a result of this, many (of) his disciples returned to their former way of life and no longer accompanied him.
67 Jesus then said to the Twelve, "Do you also want to leave?" 68 Simon Peter answered him, "Master, to whom shall we go? You have the words of eternal life. 69 We have come to believe and are convinced that you are the Holy One of God." 70 Jesus answered them, "Did I not choose you twelve? Yet is not one of you a devil?" 71 He was referring to Judas, son of Simon the Iscariot; it was he who would betray him, one of the Twelve.
You haved studied Scripture. You know these verses. I believe you to be sincere, almost alone among your FR companions. I ask that you consider these.
Even Martin luther weighed in in favor of the True Presence in the Eucharist when he said:
All three accounts of the institution of the Lord's Supper in the Gospels (Matthew 26:26-29; Mark 14:22-25; Luke 22:14-23) explicitly state that Jesus took BREAD, blessed it, broke it, and gave it to his disciples saying, "Take, eat; this [i.e., this BREAD, which I have just blessed and broken and am now giving to you] is my body." Jesus uses similar language in referring to "the cup" (of wine) as "his blood."... Perhaps the most explicit expression of this truth, however, is found in 1 Cor. 10:16-17, where Paul writes: "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? Because there is one bread, we who are many are one body, for we all partake of the one bread." Paul clearly says here that we all "partake" of "BREAD" when we receive the Lord's Supper--even as we also partake of and "participate in" the true body of Christ. And he says that we all "partake" of the wine (the cup), even as we also partake of the true blood of Christ. Similarly, in 1 Cor. 11:26, Paul says: "For as often as you eat this bread and drink the cup, you proclaim the Lord's death until he comes." Paul expressly states here ........................that those who eat this bread and drink this cup are also partaking of the true body and blood of Christ. So "real" is this participation in Christ's body and blood, in fact, that (according to Paul) those who partake of the bread and wine "in an unworthy manner" are actually guilty of "profaning the body and blood of the Lord" (1 Cor. 11:27). (Partaking of the Lord's Supper "in a worthy manner," of course, is not something that we "do" or "accomplish" on the basis of our "personal holiness" or "good works." It means receiving God's free and gracious gifts of life and forgiveness offered in the Lord's Supper in true repentance produced by the work of the Spirit through God's Law and in true faith in Christ and his promises produced by God's Spirit through the Gospel).
Who, but the devil, has granted such license of wresting the words of the holy Scripture?
Who ever read in the Scriptures, that my body is the same as the sign of my body?
or, that is is the same as it signifies? What language in the world ever spoke so?
It is only then the devil, that imposes upon us by these fanatical men.
They asked Him for a sign, saying that Moses gave them manna in the desert. If Jesus (according to them) was aspiring to the level of Moses, He should do something as big as that.
30 So they asked him, What sign then will you give that we may see it and believe you? What will you do?
31 Our ancestors ate the manna in the wilderness; as it is written: He gave them bread from heaven to eat.
32 Jesus said to them, Very truly I tell you, it is not Moses who has given you the bread from heaven, but it is my Father who gives you the true bread from heaven.
33 For the bread of God is the bread that comes down from heaven and gives life to the world.
34 Sir, they said, always give us this bread.
35 Then Jesus declared, I am the bread of life. Whoever comes to me will never go hungry, and whoever believes in me will never be thirsty.
36 But as I told you, you have seen me and still you do not believe.
And now the crowd is openly rebellious saying How can this man give us his flesh to eat?
48 I am the bread of life. 49 Your ancestors ate the manna in the wilderness, yet they died.
50 But here is the bread that comes down from heaven, which anyone may eat and not die.
51 I am the living bread that came down from heaven. Whoever eats this bread will live forever. This bread is my flesh, which I will give for the life of the world.
Note -- Jesus doesn't clear up the Metaphor, like he did in Matt. 16:512
53 Jesus said to them, Very truly I tell you, unless you eat the flesh of the Son of Man and drink his blood, you have no life in you.
54 Whoever eats my flesh and drinks my blood has eternal life, and I will raise them up at the last day.
55 For my flesh is real food and my blood is real drink.
56 Whoever eats my flesh and drinks my blood remains in me, and I in them.
57 Just as the living Father sent me and I live because of the Father, so the one who feeds on me will live because of me.
58 This is the bread that came down from heaven. Your ancestors ate manna and died, but whoever feeds on this bread will live forever.
5 When they went across the lake, the disciples forgot to take bread.So, Jesus DOES indicate when it is a metaphor and when it isn't.
6 Be careful, Jesus said to them. Be on your guard against the yeast of the Pharisees and Sadducees.
7 They discussed this among themselves and said, It is because we didnt bring any bread.
8 Aware of their discussion, Jesus asked, You of little faith, why are you talking among yourselves about having no bread?
9 Do you still not understand? Dont you remember the five loaves for the five thousand, and how many basketfuls you gathered?
10 Or the seven loaves for the four thousand, and how many basketfuls you gathered?
11 How is it you dont understand that I was not talking to you about bread? But be on your guard against the yeast of the Pharisees and Sadducees.
12 Then they understood that he was not telling them to guard against the yeast used in bread, but against the teaching of the Pharisees and Sadducees.
You cannot say that this was just bread and wine of that this is a metphor for coming and having faith in the Lord or some kind of metphor for believing in Christ because of the reaction of the Jews and the very language -- to eat one's flesh and drink the blood means to do violence on some one. You see it even in Hindi where a threat is "Mein tera Khoon pie jaongaa" or "I will drink your blood" -- and this is among vegetarians! To drink a persons blood means a serious threat of injury.
60 On hearing it, many of his disciples said, This is a hard teaching. Who can accept it?...
66 From this time many of his disciples turned back and no longer followed him.
Jesus repeats the rebuke against just thinking in terms of human logic (Calvin's main problem) by saying
61 Aware that his disciples were grumbling about this, Jesus said to them, Does this offend you?
62 Then what if you see the Son of Man ascend to where he was before!
63 The Spirit gives life; the flesh counts for nothing. The words I have spoken to youthey are full of the Spirit[e] and life.
64 Yet there are some of you who do not believe.
Just using human logic as Calvinist thought does, without God's blessings behind it fails in grace.John 6:63 does not refer to Jesus's statement of his own flesh, if you read in context but refers to using human logic instead of dwelling on God's words.
15 B<>You judge by human standards; I pass judgment on no one.
16 But if I do judge, my decisions are true, because I am not alone. I stand with the Father, who sent me.
and also 1 Cor 11:27-29
6 Is not the cup of thanksgiving for which we give thanks a participation in the blood of Christ? And is not the bread that we break a participation in the body of Christ?
How clear can Paul get? "The bread IS a participation in the body of Christ" and "who eats the bread... will have to answer for the body and blood of the Lord" This is not just mere bread and wine anymore. This is the body and blood of Christ.
27 So then, whoever eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of sinning against the body and blood of the Lord.
28 Everyone ought to examine themselves before they eat of the bread and drink from the cup.
29 For those who eat and drink without discerning the body of Christ eat and drink judgment on themselves.