Anguttara Nikaya 7.60
Kodhana Sutta: An Angry Person (extract)
translated from the Pali by Thanissaro Bhikkhu

"These seven things —
pleasing to an enemy, bringing about an enemy's aim —
come to a man or woman who is angry.
Which seven?

"There is the case where an enemy wishes of an enemy,
'O, may this person be ugly!'
Why is that? An enemy is not pleased with an enemy's good looks.
Now, when a person is angry —
overcome with anger, oppressed with anger —
then regardless of the fact that he may be well-bathed, well-anointed,
dressed in white clothes, his hair & beard neatly trimmed,
he is ugly nevertheless, all because he is overcome with anger.
This is the first thing pleasing to an enemy,
bringing about an enemy's aim,
that comes to a man or woman who is angry.

"Furthermore, an enemy wishes of an enemy,
'O, may this person sleep badly!'
Why is that? An enemy is not pleased with an enemy's restful sleep.
Now, when a person is angry —
overcome with anger, oppressed with anger —
then regardless of the fact that he sleeps on a bed spread with a white blanket,
spread with a woolen coverlet, spread with a flower-embroidered bedspread,
covered with a rug of deerskins, with a canopy overhead, or on a sofa with red
cushions at either end, he sleeps badly nevertheless, all because he is overcome
with anger.
This is the second thing pleasing to an enemy, bringing about an enemy's aim,
that comes to a man or woman who is angry.

"Furthermore, an enemy wishes of an enemy, 'O, may this person not profit!'
Why is that? An enemy is not pleased with an enemy's profits.
Now, when a person is angry —
overcome with anger, oppressed with anger —
then even when he suffers a loss, he thinks, 'I've gained a profit';
and even when he gains a profit, he thinks, 'I've suffered a loss.'
When he has grabbed hold of these ideas that work in mutual opposition [to the
truth], they lead to his long-term suffering & loss, all because he is overcome
with anger. This is the third thing pleasing to an enemy, bringing about an
enemy's aim, that comes to a man or woman who is angry.

"Furthermore, an enemy wishes of an enemy,
'O, may this person not have any wealth!'
Why is that? An enemy is not pleased with an enemy's wealth.
Now, when a person is angry —
overcome with anger, oppressed with anger —
then whatever wealth he has, earned through his efforts & enterprise,
amassed through the strength of his arm,
and piled up through the sweat of his brow —
righteous wealth righteously gained —
the king orders it sent to the royal treasury [in payment of fines levied for
his behavior] all because he is overcome with anger.
This is the fourth thing pleasing to an enemy, bringing about an enemy's aim,
that comes to a man or woman who is angry.

"Furthermore, an enemy wishes of an enemy,
'O, may this person not have any reputation!'
Why is that? An enemy is not pleased with an enemy's reputation.
Now, when a person is angry —
overcome with anger, oppressed with anger —
whatever reputation he has gained from being heedful, it falls away, all because
he is overcome with anger.
This is the fifth thing pleasing to an enemy, bringing about an enemy's aim,
that comes to a man or woman who is angry.

"Furthermore, an enemy wishes of an enemy,
'O, may this person not have any friends!'
Why is that? An enemy is not pleased with an enemy's having friends.
Now, when a person is angry —
overcome with anger, oppressed with anger —
his friends, companions, & relatives will avoid him from afar, all because he is
overcome with anger.
This is the sixth thing pleasing to an enemy, bringing about an enemy's aim,
that comes to a man or woman who is angry.

"Furthermore, an enemy wishes of an enemy,
'O, may this person, on the break-up of the body, after death, reappear in the
plane of deprivation, the bad bourn, the lower realms, in hell!'
Why is that? An enemy is not pleased with an enemy's going to heaven.
Now, when a person is angry —
overcome with anger, oppressed with anger —
he engages in misconduct with the body, misconduct with speech, misconduct with
the mind. Having engaged in misconduct with the body, misconduct with speech,
misconduct with the mind, then — on the break-up of the body, after death — he
reappears in the plane of deprivation, the bad bourn, the lower realms, in hell,
all because he was overcome with anger.
This is the seventh thing pleasing to an enemy, bringing about an enemy's aim,
that comes to a man or woman who is angry.

"These are the seven things — pleasing to an enemy, bringing about an enemy's
aim — that come to a man or woman who is angry."
http://www.accesstoinsight.org/tipitaka/an/an07/an07.060.than.html
For Free Distribution, as a gift of Dhamma, from Access to Insight and
Thanissaro Bhikkhu

Antony: Remembering this sutta today I laughed. I have a favorite classic enemy
on Buddhist forums who publicly humiliated me to thousands of people regarding
me being morally unfit to call myself a Dhamma friend, publicly derived pleasure
when I was shocked by her belief that the Buddha taught that I am suffering at
all times, and believes that Thanissaro Bhikkhu is a heretic!

I'm thinking that the Buddha meant metta as goodwill rather than lovingkindness:
that it's OK to sometimes label someone as an enemy.

With metta / Antony.