[I am re-posting this to mark his memorial in the Church's calendar today.
Requiring extreme reverence for the Blessed Eucharist
Let us attend, all clerics, to the great sin and ignorance, which certain men have over the Most Holy Body and Blood of Our Lord Jesus Christ and the Most Holy Names and His written words, which sanctify the Body.
We know that there cannot be a Body, unless first it is sanctified by the word.
For we have and see nothing corporally of the Most High Himself, in this age, except the Body and Blood, Names and words, through which we have been made and redeemed from death to life.
However let all those who minister such most holy ministries, consider within themselves— most of all those who minister indiscreetly— how vile are the chalices, corporals, and altar linens, where the Body and Blood of the Lord is sacrificed.
And by many in vile places He is abandoned, borne about in a wretched manner and received unworthily and ministered to others indiscreetly.
Even the Names and His written words are sometimes by feet trampled upon;
because the bestial man does not perceive the things that are of God.
Are we not moved in piety concerning all these things, when the pious Lord Himself offers Himself into our hands and we handle Him and receive Him each day by means of our mouth?
Or are we ignorant that we must one day come into His Hands?
Therefore let us quickly and firmly amend ourselves regarding all these things and the others;
and wherever the Most Holy Body of Our Lord Jesus Christ has been illicitly placed and abandoned, let Him be removed from that place and let Him be placed and sealed in a precious place.
Similarly let the Names and written words of the Lord, wherever they are found in unclean places, be gathered together and they ought to be placed together in an honorable place.
And we know, that we are bound above all to observe all these things according to the precepts of the Lord and the constitutions of Holy Mother Church.
And those who have not done this, let them know, that they shall render an account before the Lord on the Day of Judgment.
This having been written, so that it ought to be better observed, let them know themselves to be blest by the Lord God, who have had it copied.
[From the Writings of St. Francis of Assisi, pages 33-35]