[A]ccepting of persons in any transaction is, properly speaking, to take as a deciding factor in that transaction some aspect of the person that has nothing to do with the matter; for example, when I give a benefice to a person just because he is a noble or is handsome. For nobility or beauty have nothing to do with the question of getting a benefice. But if some aspect of the person does have something to do with the matter, then if I consider that aspect in settling the matter, I do not accept the person; for example, if I give a benefice to a person because he is good and will serve the Church well, or because he is well-educated and honourable, I am not an acceptor of persons. Therefore to accept the person is nothing other than to consider some aspect of the person that has no relation to the business. Hence, since God in His works and benefits regards nothing that pre-exists on the side of the creature-for that which pertains to the creature is an effect of His election—but takes as His measure merely what pleases His will, according to which He effects all things, and not the condition of their person, as is said in Ephesians (1:11), it is evident that He does not regard the person of man.

–  St Thomas Aquinas, Commentary on Galatians