Lactantius — Divine Institutes 6.10

I have said what is owed to God: I will now say what is to be granted to a human; although that very thing which you have granted to a human is granted to God, because a human is God's image. But still the first office of justice is to be joined with God, the second with a human. But that first is called religion, this second is named mercy or humanity. Which virtue is proper to the just and to the worshipers of God, because it alone holds the reason of common life. For God, who did not give wisdom to the other animals, generated them safer by natural defenses from assault and danger; but a human, because he shaped him naked and fragile that he might rather equip him with wisdom, gave him besides the rest this affection of piety, that human may guard, love, foster human and against all dangers both receive and offer help. The highest bond therefore among humans is humanity: which who has broken must be thought wicked and a murderer. For if we all arise from one human whom God fashioned, we are certainly of one blood and therefore it must be thought the greatest crime to hate a human even when harmful. For that reason God commanded enmities never to be made by us, always to be removed, namely that we may soften those who are enemies to us when reminded of kinship. Likewise if we all are inspired and given life by one God, what else are we than brothers, and indeed more closely joined because by souls than those who by bodies? And so Lucretius does not err when he says: 'Finally we all are sprung from heavenly seed; that same one is father to all.' Therefore they are to be held for wild beasts who harm a human, who against the right of humanity and every divine law strip, torture, kill, exile. For this kinship of brotherhood God teaches us never to do evil, always good. But what it itself is to do good, he himself also prescribes: to offer help to the pressed and laboring, to impart food to those not having. For God since he is pious willed us to be a social animal: and so in other humans we ought to think of ourselves. We do not deserve to be freed in danger if we do not help, we do not deserve help if we refuse.

Toward this part the philosophers have no precepts, inasmuch as captivated by the appearance of false virtue they have removed mercy from the human and while they will to heal have spoiled. And though the same often confess that the fellowship of human society is to be kept, by the rigidity of their inhuman virtue they plainly dissociate themselves from it. This error of theirs also must therefore be convicted who think nothing should be imparted to anyone. They have brought in not one origin and cause of founding a city, but some recount that those humans who were first born from earth, when they spent a wandering life through woods and fields and cohered by no bond of speech or right among themselves, but had leaves and grass for beds, caves and dens for homes, were prey to beasts and stronger animals. Then those who had either escaped torn or had seen neighbors torn, warned of their danger, ran down to other humans, begged protection and first by nods signified their will, then tried the beginnings of speech and by impressing names on each several things gradually completed the system of speaking. And when they saw the multitude itself must be guarded against beasts, they also began to fortify towns, that they might either make the rest of night safe for themselves or keep off the rushes and assaults of beasts not by fighting but by thrown-up mounds. O talents unworthy of humans, which have put forward these sillinesses, wretched and pitiable, who have committed their folly to letters and memory! Who when they saw that even to mute animals reason is inborn either of gathering or of seeking one another or of fleeing danger or of guarding against evil or of preparing beds and dens for themselves, still thought humans themselves could not be warned and learn except by examples what they ought to fear, guard against, do, or that they would never have met among themselves nor found a system of speaking unless beasts had eaten them. These things seemed delirious to others, as they were, and they said not the tearing of wild beasts was the cause of gathering, but rather humanity itself, and so they were gathered among themselves because humans' nature flees solitude and seeks fellowship and society.

There is not a great dispute among them, since the causes are different, the thing is the same. Both therefore could be, because it does not conflict, but still both is by no means true, because humans were not born through all the earth from earth as if sown from some dragon's teeth, as the poets say, but one human was fashioned by God and from that one all the earth was filled with the human race, by the same reason clearly as again after the flood; which certainly they cannot deny. No gathering of that sort therefore was made in the beginning nor were there ever humans on earth who beyond infancy did not speak, he will understand to whom reason is not lacking. But let us suppose those things true which idle and silly old men invent, that we may refute them by their own senses and reasons. If for this cause humans were gathered, that by mutual helps they might guard their weakness, help must therefore be given to a human who needs help. For since for the sake of protection humans have entered society with humans and have sanctioned it, to violate that covenant from the beginning of its birth among humans or not to keep it must be thought the highest crime. For who removes himself from offering help must also necessarily remove himself from receiving, because he thinks he needs no one's work who denies his own to another. But for this one who dissociates and separates himself from the body, one must live not by human rite but by beasts' custom. Which if it cannot happen, the bond of human society must therefore be kept in every way, because a human without a human can by no means live. But keeping of society is community, that is to offer help that we may be able to receive. But if, as those others argue, the gathering of humans was made for the sake of humanity itself, a human ought certainly to acknowledge a human. Which if those rude and still almost wild humans did, and did it with the system of speaking not yet established, what should we think must be done by polished humans joined among themselves by commerce of speech and of all things, who accustomed to humans cannot bear solitude?