Theories of syntax explore the distinction between antecedents and postcedents in terms of binding.
Bryan Garner calls these "remote relatives" and gives this example from the New York Times:"C-130 aircraft packed with radio transmitters flew lazy circles over the Persian Gulf broadcasting messages in Arabic to the Iraqi people that were monitored by reporters near the border.
"As Garner points out, “that were…the border” modifies “messages”, which occurs 7 words (3 of which are nouns) before.
In such cases, the antecedent is implied in the given discourse environment or from general knowledge of the world.
It is raining, where the pronoun it is semantically empty and cannot be viewed as referring to anything specific in the discourse world.
Definite pro-forms such as they and you also have an indefinite use, which means they denote some person or people in general, e.g.