Physically, it's just a mixture of olive oil and balsam, good for the skin, and even better for the scalp! As a matter of fact, balsam oil is a frequent ingredient in hair conditioner, and there is a pretty pricey line of skin care products that have olive oil as their base; they even sell a pure olive oil that is meant for skin moisturizing, and no, you don't smell like a salad after you use it.
If there's still some on your forehead, smear it into your hairline and massage well before you shampoo. But I'm surprised if there is some left, since olive oil is very similar to the composition of the oils your own skin puts out, and absorbs into the top layer of skin readily. And no, it won't clog your pores.
Olive oil is very rich in antioxidants, and helps protect your skin against wrinkling and damage from what is called 'free radicals." Free radicals have been implicated in some skin cancers. I think most people know about olive oil's superior benefits as a nutritional fat (helps boost "good cholesterol" and lowers "bad cholesterol,") plus it is superior for many cooking purposes.
Here's a hint if you want to try regular olive oil as a skin moisturizer: Wash your face, and leave it damp, then massage a few drops of olive oil into your still-moist skin, then towel off.
I suppose the ancient Church fathers intuitively knew how good these oils are, that's why they identified them to be used for the purposes of sacraments.