How is the Black Rubric related to the Eucharist?

Answer 1

The Black Rubric: "Whereas it is ordained in this Office for the Administration of the Lord's Supper, that the Communicants should receive the same kneeling; (which order is well meant, for a signification of our humble and grateful acknowledgment of the benefits of Christ therein given to all worthy Receivers, and for the avoiding of such profanation and disorder in the holy Communion, as might otherwise ensue;) yet, lest the same kneeling should by any persons, either out of ignorance and infirmity, or out of malice and obstinacy, be misconstrued and depraved: It is hereby declared, That thereby no adoration is intended, or ought to be done, either unto the Sacramental Bread or Wine there bodily received, or unto any Corporal Presence of Christ's natural Flesh and Blood. For the Sacramental Bread and Wine remain still in their very natural substances, and therefore may not be adored; (for that were Idolatry, to be abhorred of all faithful Christians;) and the natural Body and Blood of our Saviour Christ are in Heaven, and not here; it being against the truth of Christ's natural Body to be at one time in more places than one."

Basically the meaning of this "rubric," which strictly speaking is not a rubric rather a passage of instruction about the Lords Supper, is to express to people who read it that one should receive the bread and wine kneeling, not out of adoration of the presence of Christ made truly present (as the Anglican Communion does not believe in the Doctrine of Transsubstantiation), rather out of Thanksgiving for the reception of the sacrament. The main point was to attempt to convince the people of the church not to believe in the Real Presence of Christ in the Eucharist.