Here is the opening of a letter John Calvin wrote to the ministers of the church of Basle regarding the persecution in France.
GENEVA, 13th November 1537. The urgent business on account of which we have thought it right to send this person by express to you may be stated in few words. A new outbreak of the cruel rage of the ungodly has burst forth at Nismes, as the place is now called, no mean city, a town of Languedoc, against the unhappy brethren who reside there, scattered up and down, and that at a time when we might have suspected nothing of the kind. Not very long ago we had obtained letters from the town councils of Strasbourg and Basle, by which the safety and personal security of all those, who were then imprisoned throughout France on account of religion, was commended to the care of Count William. That eminent person, as was reported, had obtained of the king that they should all be set at liberty. We rested secure in this expectation, until word was brought to us, that the fire of persecution was again raging in that quarter. Two persons have been burnt, concerning the manner of whose death you will hear from the eye-witness himself, for he can relate to you in Latin what he has narrated in detail to us. Many have been thrown into prison, who are in jeopardy of their lives, unless timely opposition is made to the fury of those who, already drunk with the blood of these two victims, are not otherwise at all likely to set any bounds to their persecuting spirit. The two who suffered have shown a remarkable spirit of constancy to the very last, although their patient endurance of suffering was tried with the most exquisite cruelty. Of a truth, we may question whether the same strength of mind will be found in the others. Relief, therefore, ought to be brought to them in their present exigency, if anyhow it can be supplied, lest those may break down who are weaker in the faith. Besides, the utmost care must be taken that the blood of the godly, which is so precious in the sight of God, may not be lightly esteemed by us.
Jules Bonnet, Dr., vol. 1, Letters of John Calvin. Vol. I-IV (Bellingham, WA: Logos Research Systems, Inc., 2009), 58-59.