Knox was a Calvinist, and one has to separate Calvin from the Calvinists. On the doctrine of the Eucharist. and I refer you to the Institutes, Calvin's belief about the real presence is distinguished from that of Luther by a semantical hair. Calvin was never the rationalist that Zwingli was, and he approached the Sacrament with as much devotion as a pious Baptist does today. The difference is that the the power of the Sacrament was not in the particular faith of the communicant but in the Lord. As if Christ in heaven were chained to his throne, he denies HIs presence in the elements or even with them. Knox was only concerned to deny the mass. In his Christiantity I find nothing but the negative.
LOL. I'm not sure what Institutes you're reading, but Calvin's Institutes clearly delineate the distinction between a spiritual offering from a physical offering. Calvin believed in the former, and denounced the latter. Precisely like Knox did. Precisely as all Calvinists do.
The "hair's difference" was between Calvin and Zwingli, not Calvin and Luther. Consubstantiation is much closer to transubstantiation than the correct Scriptural understanding of a spiritual bread and body. Shedding the errors of Rome was not an easy or overnight process. It took time and strength.
Knox was only concerned to deny the mass. In his Christiantity I find nothing but the negative.
Nonsense. Knox was truly in the thick of the battle, but his hundreds of sermons were clear articulations of Biblical truth. Let's see if what Knox actually wrote differs from Calvin and the Reformed definition of the Lord's Supper...
First, we confess that it is a holy action, ordained of God, in the which the Lord Jesus, by earthly and visible things set before us, lifts us up unto heavenly and invisible things. And that when he had prepared his spiritual banquet, he witnessed that he himself was the lively bread wherewith our souls are fed unto everlasting life. And therefore, in setting forth bread and wine to eat and drink, he confirms and seals up to us his promise and communion (that is, that we shall be partakers with him in his kingdom); and he represents unto us, and makes plain to our senses, his heavenly gifts; and also gives unto us himself, to be received with faith, and not with mouth, nor yet by transfusion of substance; but so, through the virtue [power] of the Holy Ghost, that we, being fed with his flesh, and refreshed with his blood, may be renewed both unto true godliness and to immortality. And also [we confess] that herewith the Lord Jesus gathered us unto one visible body, so that we are members one of another, and make altogether one body, whereof Jesus Christ is the only Head; and, finally, that by the same sacrament, the Lord calls us to remembrance of his death and passion, to stir up our hearts to praise his most holy name. Furthermore, we acknowledge that this sacrament ought to be come unto reverently, considering there is exhibited and given a testimony of the wonderful society and knitting together of the Lord Jesus and of the receivers; and also, that there is included and contained in this sacrament, [a testimony] that he will preserve his kirk. For herein we are commanded to show the Lord's death until he come (1 Cor. 11:26). Also we believe that it is a confession, wherein we show what kind of doctrine we profess; and what congregation we join ourselves unto; and likewise, that it is a bond of mutual love amongst us. And, finally, we believe that all the comers unto this holy Supper must bring with them their conversion unto the Lord, by unfeigned repentance in faith; and in this sacrament receive the seals and conrmation of their faith; and yet must in nowise think that for this work's sake their sins are forgiven. And as concerning these words, Hoc est corpus meum, "This is my body" (1 Cor. 11:24; Matt. 26:26; Mark 14:22; Luke 22:19), on which the Papists depend so much, saying that we must needs believe that the bread and wine are transubstantiated unto Christ's body and blood: we acknowledge [declare] that it is no article of our faith which can save us, nor which we are bound to believe upon pain of eternal damnation. For if we should believe that his very natural body, both flesh and blood, were naturally in the bread and wine, that should not save us, seeing many believe that, and yet receive it to their damnation. For it is not his presence in the bread that can save us, but his presence in our hearts, through faith in his blood, which has washed out our sins, and pacified his Father's wrath towards us. And again, if we do not believe his bodily presence in the bread and wine, that shall not damn us, but the absence out of our hearts through unbelief. Now, if they would here object, that though it be truth, that the absence out of the bread could not damn us, yet are we bound to believe it because of God's word, saying, "This is my body" (1 Cor. 11:24); which who believes not, as much as in him lies, makes God a liar; and, therefore of an obstinate mind not to believe his word, may be our damnation: To this we answer, that we believe God's word, and confess that it is true, but not so to be understood as the Papists grossly affirm. For in the sacrament we receive Jesus Christ spiritually, as did the fathers of the Old Testament, according to St. Paul's saying (1 Cor. 10:3-4). And if men would well weigh, how that Christ, ordaining his holy sacrament of his body and blood, spoke these words sacramentally, doubtless they would never so grossly and foolishly understand them, contrary to all the scriptures, and to the exposition of St. Augustine, St. Jerome, Fulgentius, Vigilius, Origen, and many other godly writers." "Here is briefly declared in a summary, according to the holy scriptures, what opinion we Christians have of the Lord's Supper, called the sacrament of the body and blood of our Saviour Jesus Christ.
If you wish to read what Calvin wrote about the Lord's Supper...
Thus it is with the communion which we have in. the body and blood of the Lord Jesus. It is a spiritual mystery which can neither be seen by the eye nor comprehended by the human understanding... Hence also we see how those to whom God has given the knowledge of his truth should differ from the Papists. First, they cannot doubt that it is abominable blasphemy to regard the Mass as a sacrifice by which the forgiveness of sins is purchased for us; or rather, that the priest is a kind of mediator to apply the merit of Christ's passion and death to those who purchase his mass, or are present at it, or feel devotion for it. On the contrary, they must hold decidedly that the death and suffering of the Lord is the only sacrifice by which the anger of God has been satisfied, and eternal righteousness procured for us; and, likewise, that the Lord Jesus has entered into the heavenly sanctuary in order to appear there for us, and intercede in virtue of his sacrifice. Moreover, they will readily grant, that the benefit of his death is communicated to us in the Supper, not by the merit of the act, but because of the promises which are given us, provided we receive them in faith. Secondly, they should on no account grant that the bread is transubstantiated into the body of Jesus Christ, nor the wine into his blood, but should persist in holding that the visible signs retain their true substance, in order to represent the spiritual reality of which we have spoken. Thirdly, they ought also to hold for certain, that the Lord gives us in the Supper that which he signifies by it, and, consequently, that we truly receive the. body and blood of Jesus Christ. Nevertheless they will not seek him as if he were enclosed under the bread, or attached locally to the visible sign. So far from adoring the sacrament, they will rather raise their understandings and their hearts on high, as well to receive Jesus Christ, as to adore him..."...Now, if it be asked whether the bread is the body of Christ and the wine his blood, we answer, that the bread and the wine are visible signs, which represent to us the body and blood, but that this name and title of body and blood is given to them because they are as it were instruments by which the Lord distributes them to us. This form and manner of speaking is very appropriate. For as the communion which we have with the body of Christ is a thing incomprehensible, not only to the eye but to our natural sense, it is there visibly demonstrated to us. Of this we have a striking example in an analogous case. Our Lord, wishing to give a visible appearance to his Spirit at the baptism of Christ, presented him under the form of a dove. St. John the Baptist, narrating the fact, says, that he saw the Spirit of God descending. If we look more closely, we shall find that he saw nothing but the dove, in respect that the Holy Spirit is in his essence invisible. Still, knowing that this vision was not an empty phantom, but a sure sign of the presence of the Holy Spirit, he doubts not to say that he saw it, (John i. 32,) because it was represented to him according to his capacity.
At the heart of Rome's error is its insistence that the mass is a recurring sacrifice. Calvin rightly saw this as blasphemy...
The opinion that the Supper is a sacrifice derogates from that of Christ, and must therefore be condemned as devilish. That it does so derogate is notorious. For how can we reconcile the two things, that Jesus Christ in dying offered a sacrifice to his Father by which he has once for all purchased forgiveness and pardon for all our faults, and that it is every day necessary to sacrifice in order to obtain that which we ought to seek in his death only? This error was not at first so extreme, but increased by little and little, until it came to what it now is. It appears that the ancient fathers called the Supper a sacrifice; but the reason they give is, because the death of Christ is represented in it. Hence their view comes to this—that this name is given it merely because it is a memorial, of the one sacrifice, at which we ought entirely to stop. And yet I cannot altogether excuse the custom of the early Church. By gestures and modes of acting they figured a species of sacrifice, with a ceremony resembling that which existed under the Old Testament, excepting that instead of a beast they used bread as the host. As that approaches too near to Judaism, and does not correspond to our Lord's institution, I approve it not. For under the Old Testament, during the time of figures, the Lord ordained such ceremonies, until the sacrifice should be made in the person of his well-beloved Son, which was the fulfilment of them. Since it was finished, it now only remains for us to receive the communication of it. It is superfluous, therefore, to exhibit it any longer under figure.... "The first error is this -- While the Lord gave us the Supper that it might be distributed amongst us to testify to us that in communicating in his body we have part in the sacrifice which he offered on the cross to God his Father, for the expiation and satisfaction of our sins—men have out of their own head invented, on the contrary, that it is a sacrifice by which we obtain the forgiveness of our sins before God. This is a blasphemy which it is impossible to bear. For if we do not recognise the death of the Lord Jesus, and regard it as our only sacrifice by which he has reconciled us to the Father, effacing all the faults for which we were accountable to his justice, we destroy its virtue. If we do not acknowledge Jesus Christ to be the only sacrifice, or, as we commonly call it, priest, by whose intercession we are restored to the Father's favour, we rob him of his honour and do him high injustice.
A good understanding by Calvin of the real and imagined differences put forth regarding the Lord's Supper is found here...
It is well known that Luther and those with whom he disagreed were prudent men, equipped with singular gifts of God. They were all in remarkable agreement about the whole substance of the faith. They were unanimous in their teaching about what the proper and sincere worship of God should be, and they endeavored to cleanse it of countless superstitions and idolatries and to free it from the corrupt inventions of men. They rejected reliance on works, by which men had been intoxicated and indeed bewitched, and taught the restoration of total salvation in the grace of Christ. They have magnificently lifted up the virtue of Christ, after it had either fallen and lain prostrate or been submerged and hidden from view. Those men do not differ in their teaching about what is the true method of invocation, what is the nature and essence of penitence from which faith arises and produces certain fruits, and what is the legitimate government of the Church. Only on the symbols themselves was there any disagreement. Yet I deliberately venture to assert that, if their minds had not been partly exasperated by the extreme vehemence of the controversies, and partly possessed by wrong suspicions, the disagreement was not so great that conciliation could not easily have been achieved. Even if, because of the vehemence of that dispute, the controversy could not have been resolved properly, is there anything to prevent the plain truth being heard at least now, as in the calm after the storm? We are all very much in agreement about what the true use of the sacraments is. We all teach in common that the sacraments have been instituted in order that they may seal the promises of God to our hearts, that they may be supports for our faith and testimonies of the divine grace. We clearly point out that they are not empty or bare and dead forms [figuras] since their use is efficacious by the power of the Holy Spirit; and by the secret virtue of the Holy Spirit, God is really offering everything that he shows in them. So we acknowledge that the bread and wine in the Holy Supper are not empty pledges of that communication which believers have with Christ, their head, because our souls enjoy him as spiritual nourishment. Everywhere there is agreement about the teaching on all these points. Why then do proud men find such a stumbling block in this connection that it bars the way to the gospel?..."After Luther on the one hand, and Œcolompadius and Zwingli on the other, were successful in their strenuous efforts to re-establish the rule of Christ, there arose that unhappy dispute about the Holy Supper of the Lord, and a great many others have been drawn into association with them. It must be more a source of grief than surprise that that conflict among the foremost leaders causes alarm to overtake beginners. However, so that these same beginners may not be unduly perturbed, they must be warned that it is an old trick of Satan's to rush otherwise prudent servants of God into controversies with each other so that he may hinder the course of sound doctrine. Who wishes to yield of his own accord to Satan's crafty ways? Thus Paul's quarrel with Barnabas reached a violent climax (Acts 15:39). Thus Paul's similar disagreement with Peter broke out into open conflict (Gal. 2:11). In the case of those three men everyone recognizes what I have mentioned — the stratagem of Satan. In the present situation, when it is a question of their own salvation, why are they blind? Someone will object that those were not controversies about doctrine. Why? When certain men were pressing the ceremonies of the Mosaic law, was not this a question of doctrine (Gal. 2:12)? Yet the split was carried so far that it rent nearly all the churches. Or will they say that it was right for the gospel to be rejected on account of that disturbance?