If you are going to tell me that we don't need to dwelling upon Abram, but rather upon Abram's God, spend more than 2% of the next two hours of teaching showing me Abram's God and less than 98% showing me Abram.
Illustrations separate the almost good from the truly excellent. There is a world of difference between great stories and word pictures that enable me to understand clearly the most challenging truths of great texts.
If you have arrived at a contestable conclusion that the text itself doesn't clearly state, don't build a significant portion of your sermon upon it. Don't go on to make a habit of this.
If you are going to scold people for obeying Scripture in a particular way, take them to that Scripture, and explain how it is actually asking to be obeyed. If you can't do that clearly, don't scold in the first place.