Both sources refer to claims by pagans that Christians used dogs in their shameless rites. The accusation is that dogs are tied to candles and are provoked to run off and thereby extinguishing the source of light, at which point an incestuous orgy begins.
Tertullian, Ad nationes:
http://www.earlychristianwritings.com/t ... ian06.html
For no doubt, when any desire initiation in the mysteries, their custom is first to go to the master or father of the sacred rites. Then he will say (to the applicant), You must bring an infant, as a guarantee for our rites, to be sacrificed, as well as some bread to be broken and dipped in his blood; you also want candles, and dogs tied together to upset them, and bits of meat to rouse the dogs. Moreover, a mother too, or a sister, is necessary for you. What, however, is to be said if you have neither? I suppose in that case you could not be a genuine Christian...
I am now come to the hour for extinguishing the lamps, and for using the dogs, and practising the deeds of darkness...
Minucius Felix, Octavius:
http://www.earlychristianwritings.com/t ... avius.html
Can anyone shed any light (no pun intended!) on this practice? I can see how the accusation of "Christians eat flesh and drink blood in their rites" might develop, but not the accusation of dogs being used to extinguish candles to start orgies. Any thoughts?