An interesting dichotomy is that we are told that you cannot judge a book by it's cover, but every book publisher's marketing department wants you to do exactly that. Back in the day all books were hardback and their covers were typically drab earth tones with the title and author embossed on the spine. It was indeed a truth that you could not judge a book purely by it's cover and the spine was required to be able to identify it. But these days, the publishers strongly desire that you should be able to judge their books by their covers. Great effort is taken to ensure that every aspect of the cover (pictures, typography, text, color scheme etc etc) will grab your attention and tell you that the book is interesting and you should purchase it.

Of course, you still can't really judge a book by it’s cover, because while that cover may be colorful and intriguing, covers are generally designed by someone other than the author. The quality of the cover is not connected to the quality of the internal material. An exciting story could have a drab cover, while an exciting cover could be wrapped around a shallow and meandering story. No matter how much a marketing department would push you to do so, be wary of judging a book by its cover. Let's expand that to a more general life principle and be careful before judging anything and more importantly anyone, by initial external impressions. I'm pretty sure there's a spiritual principle that goes along with this. Oh, look, James, ever the dispenser of wisdom, enjoins us on this exact topic:

For if there come unto your assembly a man with a gold ring, in goodly apparel, and there come in also a poor man in vile raiment; And ye have respect to him that weareth the gay clothing, and say unto him, Sit thou here in a good place; and say to the poor, Stand thou there, or sit here under my footstool: Are ye not then partial in yourselves, and are become judges of evil thoughts?

James 2:2-4

There is much to unpack here, but this time I'm going to only chase down the one point. No matter how someone arrives in your life, you're going to notice their metaphorical book cover. Perhaps it's flashy, maybe it's drab, some may like wearing more black than you believe a human being should have in their wardrobe and others may walk stylistically to a drummer of their own beat. Regardless, these people have souls and Jesus loves them and wishes to love them through you as well. We are to receive them identically and equally enthusiastically. The eternal destination of their soul may be affected by how you receive them. Sure, you may believe that the well dressed person will be more able to give generously to the church and that the drab one will be a net drain on the coffers, but I can assure you that I have seen the opposite so often, that I have long dropped such expectations from my reactions. Reacting to surface level evidence is the least loving response we can give someone. Get to know them and only then judge them on their character.