To fix a truth firmly in the hearer's mind requires that we state it simply.
I'm not talking about trivializing truth. But you can be simple without being simplistic.
There's no need to try and impress an audience through the obscurity of our language. In fact, I'd go so far as to say that you really don't understand your subject unless you can express it clearly to others.
New Testament scholars, for example, speak of Weltanschauung, Sitz im Leben, Heilsgeschichte, and Ausgangstext. All well and good I suppose when speaking to other scholars.
But when we're addressing an audience less familiar with our discipline, we must step down from our abstraction and talk about "world view," "setting in life," "salvation history," and "initial text." If we fail to do so we may get high marks as scholars but fail as communicators.
If we're not careful, we'll use jargon to impress rather than to inform. Terms like pneumatology, existentialism, and hamartiology become unnecessary barriers to communication.
In short: Never overestimate your audience's religious vocabulary.