And the elder or priest shall administer it; and after this manner shall he administer it-- he shall kneel with the church and call upon the Father in solemn prayer, . . . (D&C 20:76)
While reading the minutes of the Salt Lake School of the Prophets, one topic that gets discussed here and there is whether the entire congregation should kneel during the blessing of the bread and wine (now water). The following are from the minutes dated February 16, 1874:
Elder L[orenzo] D[ow] Young enquired if it ^whether^ was not right ^necessary^ for those who ^receive, and also^ administer the Sacrament to kneel with the congregation, as per Doc[trine] & Cov[enants].
Prest D H Wells said since that book was published, the Church has grown, and instructions given in an early day when all the members could meet in a small room, were not always suited to its after growth, so that we must not regard them as being binding under all circumstances. Even Joseph [Smith] before his death blessed the Sacrament in a standing position, and the members meeting in a Grove, where it would not be wisdom to kneel.
Elder E[lias] Morris enquired if it was not right for any member doing wrong such as getting drunk, to make a public confession of that wrong before partaking of the Sacrament.
Prest Wells said it would not be wisdom especially in a mixed audience, as it would do more harm than good, but if a man sin let him be dealt with according to the law of the Church. (Salt Lake School of the Prophets, 1867-1883 [ed. Devery S. Anderson; Salt Lake City: Signature Books, 2018], 432-22)