The source of an argument has no influence on its veracity. If a talking pile of baked hams says 2 + 2 = 4, indeed it remains true that 2 + 2 = 4. You might want to figure out why you are suffering from severe hallucinations, but once you've gotten that squared away, you'll find the equation still holds up.
Considering the source important is the ad hominem fallacy. The only reason consideration of source is justified is because an individual does not have an infinite amount of time to fully analyze every argument. Paying attention to the source is therefore a matter credibility for the sake of efficiency and expediency. Such corner cutting unfortunately comes at the expense of accuracy and ought to be avoided where feasible.