to call out a questionable statement as a quote from another source such as a television show, movie, magazine, book or other media.
to argue that a radical statement made by another was from something that person viewed or experienced.
In other words, to say that what somebody said was so fucked up or stupid or just scary that it better have come from something else and not be original.
someone's words going to far and someone else calling them to be fake to hope that they are not being honest and/or serious
Guy 1: i like fat bitches, fat and old, with saggy tits
Guy 2: you better be quotin'
Perv: 12 is the perfect age for girls. 12 man.
Other Guy: I don't know what your problem is man, but you better be quotin'
Aryan 1: I love hitler so much and the KKK too, plus im a murderer.
Aryan 2: You better be quotin'.