Quoting others: content or soure?

I am going back through my rough draft to do self-editing and potentially add quotations. I just read an appropriate quotation, but I seriously doubt that any of my readers will have heard of the source. I know when I read academic work, the source matters. Should I ignore this person because I don’t know that anyone will know who he is and therefore not care about what he said? Or, is it fine to use an appropriate quote even if readers don’t know that author. Since I’m writing about prayer, my readers are likely to know who Tim Keller is, if I quote him. They are unlikely to know who Demetrius Dumm is. What do you think? Thanks.

Ken