Below is the 1689 London Baptist Confession of Faith on the Lord’s Supper (Holy Communion or Eucharist, or whatever you’re use to calling it).
Chapter 30: Of the Lord’s Supper
1. The supper of the Lord Jesus was instituted by him the same night wherein he was betrayed, to be observed in his churches, unto the end of the world, for the perpetual remembrance, and shewing forth the sacrifice of himself in his death, confirmation of the faith of believers in all the benefits thereof, their spiritual nourishment, and growth in him, their further engagement in, and to all duties which they owe to him; and to be a bond and pledge of their communion with him, and with each other.
( 1 Corinthians 11:23-26; 1 Corinthians 10:16, 17,21 )
2. In this ordinance Christ is not offered up to his Father, nor any real sacrifice made at all for remission of sin of the quick or dead, but only a memorial of that one offering up of himself by himself upon the cross, once for all; and a spiritual oblation of all possible praise unto God for the same. So that the popish sacrifice of the mass, as they call it, is most abominable, injurious to Christ’s own sacrifice the alone propitiation for all the sins of the elect.
( Hebrews 9:25, 26, 28; 1 Corinthians 11:24; Matthew 26:26, 27 )
3. The Lord Jesus hath, in this ordinance, appointed his ministers to pray, and bless the elements of bread and wine, and thereby to set them apart from a common to a holy use, and to take and break the bread; to take the cup, and, they communicating also themselves, to give both to the communicants.
( 1 Corinthians 11:23-26, etc. )
4. The denial of the cup to the people, worshipping the elements, the lifting them up, or carrying them about for adoration, and reserving them for any pretended religious use, are all contrary to the nature of this ordinance, and to the institution of Christ.
( Matthew 26:26-28; Matthew 15:9; Exodus 20:4, 5 )
5. The outward elements in this ordinance, duly set apart to the use ordained by Christ, have such relation to him crucified, as that truly, although in terms used figuratively, they are sometimes called by the names of the things they represent, to wit, the body and blood of Christ, albeit, in substance and nature, they still remain truly and only bread and wine, as they were before.
( 1 Corinthians 11:27; 1 Corinthians 11:26-28 )
6. That doctrine which maintains a change of the substance of bread and wine, into the substance of Christ’s body and blood, commonly called transubstantiation, by consecration of a priest, or by any other way, is repugnant not to Scripture alone, but even to common sense and reason, overthroweth the nature of the ordinance, and hath been, and is, the cause of manifold superstitions, yea, of gross idolatries.
( Acts 3:21; Luke 14:6, 39; 1 Corinthians 11:24, 25 )
7. Worthy receivers, outwardly partaking of the visible elements in this ordinance, do then also inwardly by faith, really and indeed, yet not carnally and corporally, but spiritually receive, and feed upon Christ crucified, and all the benefits of his death; the body and blood of Christ being then not corporally or carnally, but spiritually present to the faith of believers in that ordinance, as the elements themselves are to their outward senses.
( 1 Corinthians 10:16; 1 Corinthians 11:23-26 )
8. All ignorant and ungodly persons, as they are unfit to enjoy communion with Christ, so are they unworthy of the Lord’s table, and cannot, without great sin against him, while they remain such, partake of these holy mysteries, or be admitted thereunto; yea, whosoever shall receive unworthily, are guilty of the body and blood of the Lord, eating and drinking judgment to themselves.
( 2 Corinthians 6:14, 15; 1 Corinthians 11:29; Matthew 7:6 )
Apart from the obvious archaic expressions here and there, and the fact that it is patterned after the earlier Westminster Confession, however reveals, to echo noted reformed theologian J.I. Packer, that these Baptists ministers of the mid-to-late 17th century–indeed took the Lord’s Supper seriously.
Of course not everyone will agree with all of the above. But it must be noted that it was not compiled in a vacuum. Rather, such came out of the crucible of controversies and constant persecution because of its very contents (along with baptism).
It also must be noted, according to paragraph 7 above, that these Baptists were no mere memorialists, contrary to the belief of many (for the Confession in its entirety, see here).