request, question, investigate
訊 centers on seeking information through words: asking a question, making a request, or investigating to find out something.
訊 combines 言 (speech) with 卂, which likely contributes a sound element. The character expresses questioning or investigating through spoken inquiry.
Words (言) fly out like swift messengers (卂) to ask questions and investigate. Picture a reporter rapidly firing questions to get the facts.
For ジン, imagine a genie (ジン) appearing when you ask a question: your request summons the genie, and ジン is the sound of the answer.