Warlocks with the Great Old One patron get the Awakened Mind feature at 1st level (PHB, p. 110), which allows them to telepathically speak to any creature they can see within 30 feet. Part of the description says:
You don't need to share a language with the creature for it to understand your telepathic utterances, but the creature must be able understand at least one language.
Does this mean that the recipient of a message sent by a Warlock using Awakened Mind is receiving the core thought itself, since they don't even need to be able to understand the language that the Warlock uses?
As an example, let's say a Warlock decides to mess around with NPCs -- or PCs for that matter -- by constantly barraging them with Awakened Mind... and let's go further by saying this Warlock speaks Abyssal, Infernal and other "otherworldly" languages.
If said Warlock decides to transmit in Abyssal, which would probably sound like hideous demonspeak and would freak the heck out of many people, to, say, a farmer, is that farmer "hearing" Abyssal or are they hearing the actual content of the thought in whatever language they understand (presumably Common)?