"The same [elder] said: 'It is not good to keep company with the iniquitous [(Οὐ συμφέρει μετὰ παρανομούντων κολλᾶσθαι)], neither in church nor in the marketplace; neither in the council nor in court nor anywhere else at all. One should totally abstain from the company of the iniquitous [(Χρὴ γὰρ εἰς τὸ παντελὲς τῆς τῶν παρανομούντων κοινωνίας απέχεσθαι)] for every one of them deserves to be avoided and is a partaker of eternal punishment."
Anonymous saying of the Desert Fathers no. 737. The anonymous sayings of the Desert Fathers: a select edition and complete English translation,ed. & trans. John Wortley (Cambridge: Cambridge University Press, 2013), 590-591.
Yes, there is this emphasis in the Desert Fathers, too (though it must be admitted that κολλᾶσθαι, for example, can be a much stronger word than simply "to keep company").