Selections from St Maximos on Love. Emphasis mine.
The one who has his mind fixed on the love of God disdains all visible things and even his own body as alien.
The one who loves God cannot help but love also every man as himself even though he is displeased by the passions of those who are not yet purified. Thus when he sees their conversion and amendment, he rejoices with an unbounded and unspeakable joy.
The one who sees a trace of hatred in his own heart through any fault at all toward any man whoever he may be makes himself completely foreign to the love of God, because love for God in no way admits hatred for man.
"The one who loves Me," says the Lord, "will keep My Commandments" and "This is my commandment, that you love one another." Therefore the one who does not love his neighbor is not keeping the Commandments, and the one who does not keep the Commandments is not able to love the Lord.
Blessed is he who can love all men equally.
You have not yet acquired perfect love if your regard for people is still swayed by their characters - for example, if, for some particular reason, you love one person and hate another, or if for the same reason you sometimes love and sometimes hate the same person.
Perfect love does not split up the single human nature, common to all, according to the diverse characteristics of individuals; but, fixing attention always on this single nature, it loves all men equally. It loves the good as friends and the bad as enemies, helping them, exercising forbearance, patiently accepting whatever they do, not taking the evil into account at all but even suffering on their behalf if the opportunity offers, so that, if possible, they too become friends. If it cannot achieve this, it does not change its own attitude; it continues to show the fruits of love to all men alike. It was on account of this that our Lord and God Jesus Christ, showing His love for us, suffered for the whole of mankind and gave to all men an equal hope of resurrection, although each man determines his own fitness for glory or punishment.
He who gives alms in imitation of God does not discriminate between the wicked and the virtuous, the just and the unjust, when providing for men's bodily needs. He gives equally to all according to their need, even though he prefers the virtuous man to the bad man because of the probity of his intention.
Men love one another, commendably or reprehensibly, for the following five reasons; either for the sake of God, as the virtuous man loves everyone and as the man not yet virtuous loves the virtuous ; or by nature, as parents love their children and children their parents; or because of self-esteem, as he who is praised loves the man who praises him; or because of avarice, as with one who loves a rich man for what he can get out of him; or because of self-indulgence, as with the man who serves his belly and his genitals. The first of these is commendable, the second is of an intermediate kind, the rest are dominated by passion.
If there are some men you hate and some you neither love nor hate, and others you love strongly and others again you love but moderately, recognize from this inequality that you are far from perfect love. For perfect love presupposes that you love all men equally.
For him who is perfect in love and has reached the summit of dispassion there is no difference between his own or another's, or between Christians and unbelievers, or between slave and free, or even between male and female. But because he has risen above the tyranny of the passions and has fixed his attention on the single nature of man, he looks on all in the same way and shows the same disposition to all. For in him there is neither Greek nor Jew, male nor female, bond nor free, but Christ who 'is all, and in all' (Col. 3:11; cf. Gal. 3:28).