In Irenaeus, Adversus haereses IV 27-30 we find an unknown Asian presbyter who’s work served Irenaeus as one of his sources about Marcion. The presbyter does not only provide ‘an apology for the Old Testament with the intention to demonstrate that the two Testaments speak of one and the same God’, but also gives us a hidden insight into Marcion's business, perhaps he was even a former employee of Marcion, before he became a believer.
The Presbyter develops his subtle arguments with constant reference to the letters of the Apostle Paul as his main authority and to Lord’s sayings, taken mainly from Matthew, but also from Luke. The only time where he refers to a parable of the Lord (Matth. 25:14-30 // Luke 19:12-28), it is within the report about his interlocutors. The Gospel narratives, therefore, seem to him to be of lesser authority than the Lord’s oracles. Sebastian Moll is correct in his observation that in the opening part of the excerpt from the presbyter (Iren., Adv. haer. IV 27,4) not only anti-Marcionite arguments, but also those of ‘a Valentinian opponent’ are displayed. And yet, Marcion is the major, and in Adv. haer. 28-30 the sole target. We even find a passage which may have been minted on Marcion:
For in some cases there follows us a small, and in others a large amount of property, which we have acquired from the mammon of unrighteousness. For from what source do we derive the houses in which we dwell, the garments in which we are clothed, the vessels which we use, and everything else ministering to our every-day life, unless it be from those things which, when we were Gentiles, we acquired by avarice, or received them from our heathen parents, relations, or friends who unrighteously obtained them?—not to mention that even now we acquire such things when we are in the faith. For who is there that sells, and does not wish to make a profit from him who buys? Or who purchases anything, and does not wish to obtain good value from the seller? Or who is there that carries on a trade, and does not do so that he may obtain a livelihood thereby? And as to those believing ones who are in the royal palace, do they not derive the utensils they employ from the property which belongs to Cæsar; and to those who have not, does not each one of these [Christians] give according to his ability? … And [these objectors] allege that [the Israelites] acted dishonestly, because, forsooth, they took away for the recompense of their labours, as I have observed, unstamped gold and silver in a few vessels; while they say that they themselves (for let truth be spoken, although to some it may seem ridiculous) do act honestly, when they carry away in their girdles from the labours of others, coined gold, and silver, and brass, with Cæsar’s inscription and image upon it. If, however, a comparison be instituted between us and them, [I would ask] which party shall seem to have received [their worldly goods] in the fairer manner? Will it be the [Jewish] people, [who took] from the Egyptians, who were at all points their debtors; or we, [who receive property] from the Romans and other nations, who are under no similar obligation to us? Yea, moreover, through their instrumentality the world is at peace, and we walk on the highways without fear, and sail where we will… For whatsoever we acquired from unrighteousness when we were heathen, we are proved righteous, when we have become believers, by applying it to the Lord’s advantage.
It is probably an intrinsic criticism of Marcion’s wealth to call the ‘large amount of property’ being ‘acquired from the mammon of unrighteousness’, meaning a profit making business, ‘acquired by avacrice’, or inheritance ‘from our heathen parents, relations, or friends who unrighteously obtained them’. That he adds that ‘even now we acquire such things when we are in the faith’ may hint at Marcion who, then, would have carried on with his maritime trade and business: ‘For who is there that sells, and does not wish to make a profit from him who buys? Or who purchases anything, and does not wish to obtain good value from the seller?’ And he seems to have obtained his ‘livelihood thereby’, and perhaps, had also the support by the royal palace, as already Peter Lampe suspected with regards to the special payments he received from the palace for his trade. Moreover, the presbyter seems to have been well acquainted with Marcion’s trade, as he mentions that he has ‘observed, unstamped gold and silver in a few vessels’ being carried, and that he earned ‘coined gold, and silver, and brass, with Caesar’s inscription and image upon it’, hence made money ‘from the labours of others’, his employees, amongst which the presbyter – before he has become a believer – counts himself (‘we, [who receive property] from the Romans and other nations … through their instrumentality the world is at peace, and we walk on the highways without fear, and sail where we will’). Interestingly, at the end of the passage, the presbyter rectifies his earlier involvement in the business, while he criticises his opponent Marcion who still trades in it, when he states: ‘For whatsoever we acquired from unrighteousness when we were heathen, we are proved righteous, when we have become believers, by applying it to the Lord’s advantage’.
 See Iren., Adv. haer. IV 27-32, or if one follows S. Moll, The Arch-heretic (2010), 17-21, than at least Adv. haer. IV 28-30 is directed against Marcion.
 See S. Moll, The Arch-heretic (2010), 18f. who highlights the idea that the maker of the world ‘originated from degeneracy’ (‘in diminutione’) as being not by Marcion.
 Iren., Adv. haer. IV 30,2f.