410. Since charity itself resides in the internal man, the seat of the good will, and is from there in the external, the seat of good actions, it follows that it is the internal man who is to be loved, and the external man as a consequence. It also follows that a person should be loved for the quality of good there is in him; good itself therefore is essentially the neighbour. This can be illustrated by these examples. When anyone chooses from three or four persons a steward to run his household, or to be a servant, does he not investigate that person's internal man, and choose one who is honest and faithful, and so love him? Similarly a king or magistrate chooses from three or four candidates one who is suitable for office and rejects one who is unsuitable, however fine he looks and however much he speaks and acts to curry favour.
[2] Since therefore every person is the neighbour, and people display infinite variety, and each of them is to be loved as the neighbour in accordance with the good in him, it is clear that love towards the neighbour has genera and species, as well as degrees. Now because the Lord is to be loved above all else, it follows that the degrees of that love are to be measured by love to Him; in other words, by how much of the Lord or what is from the Lord he possesses in himself, for this is a measure of how much good he possesses too, because all good comes from the Lord.
[3] But because these degrees exist in the internal man, who is rarely to be discerned in the world, it is sufficient for one to love the neighbour in terms of the degrees one does know. After death these are clearly perceived, for in that world the affections of the will and the resulting thoughts of the understanding create a spiritual sphere around them, which is felt in various ways. But in the world that spiritual sphere is absorbed by the material body and is enveloped in the natural sphere which then emanates from the person. The existence of degrees of love towards the neighbour is proved by the Lord's parable about the Samaritan, who had pity on the man wounded by robbers, though the priest and the Levite saw him and passed by; and when the Lord asked which of the three would seem to have been the neighbour, he received the reply, 'The one who had pity' (Luke 10:30-37).