Hatred is indeed never appeased by hatred here.
It is appeased by non-hatred - this law is eternal.

na         hi     verena     verāni     sammanti     idha kudācanaṃ
|             |         |               |               |               |           |
neg.     part.   N.n.         N.n.      V.act.in.       Adv.    Adv.
|_______|     Ins.Sg.    Nom.Pl.    3.Pl.pres.       |______|
      |_________|               |________|                      |
              |_________________|                              |
                             |__________________________|

List of Abbreviations

averena ca     sammanti         esa         dhammo     sanantano
|             |            |                  |                 |                  |
N.n.    conj.   V.act.in.      Pron.m.         N.m.         Adj.m.
Ins.Sg.    |      3.Pl.pres.    Nom.Sg.      Nom.Sg.     Nom.Sg.
|_______|_______|                 |__________|                  |
       |___|                                       |________________|
          |________________________________|

na: neg.: not.

hi: part.: indeed.

verena: vera-, N.n.: hatred, enmity. Ins.Sg. = verena.

verāni: vera-, see above. Nom.Pl. = verāni.

sammanti: the verb sam- (to be appeased). 3.Pl.act.in.pres. = sammanti.

idha: Adv.: here, in this place, in this world.

Euphonic combination: sammanti + idha = sammantīdha.

List of Abbreviations

kudācanaṃ: Adv.: at any time (na kudācanaṃ, as in this verse: never).

averena: avera-, N.n.: non-hatred. The word vera- (see above) with the negative prefix a-. Ins.Sg. = averena.

ca, conj.: and.

sammanti: see above.

esa: Pron. etad-, this. Nom.Sg.m = esa.

dhammo: dhamma-, N.m.: this word has many meanings (for some of them see Vandanā 2 (tisaraṇa) or DhP 1 and 2). In this context it means "law". Nom.Sg. = dhammo.

sanantano: sanantana-, Adj.: eternal, everlasting. Nom.Sg.m. = sanantano.

List of Abbreviations

    The first line forms a separate sentence in this verse. The subject of the first sentence is verāni (hatred, note the plural form here) which is in nominative plural. The verb sammanti (are appeased) is negated by the negative particle "na" (not) which stands at the beginning of the sentence. The verb is in 3rd person plural, present tense, active voice and indicative mood. The word verena (by hatred, instrumental singular) is an attribute to the verb. There are two adverbs idha (here) and kudācanaṃ (ever; this is negated by the negative particle na). The sentence is stressed by the particle hi (indeed).

    In the second sentence (averena ca sammanti) subject is omitted (it is the word verāni from the previous line) and the verb is again sammanti. The word averena (by non-hatred) forms an attribute to the verb and it is in instrumental singular. The conjunction ca (and) connects this sentence to the previous one.

    The last sentence (esa dhammo sanantano) has as its subject the word esa (this, nominative singular). The verb is omitted, thus implying the verb "to be". The word dhammo (law, nominative singular) forms an attribute to the verb. This word has an attribute itself -- the word sanantano (eternal, nominative singular).

    This pair of verses (DhP 5 and 6) is very close in meaning to the previous pair (DhP 3 and 4). Again, a very simple truth, that most of the religions in the history have stressed again and again. The only cure for hatred is the abstention from it. Never can we stop people from hating us by hating them. In this way, mutual hatred will rise -- often to the point when hatred gives way to violence.

    The only way to stop this chain of hatred is to stop hating, of course. As the verse says, this is an eternal law. It was always so and always will be. One can only wish that we could remember this verse in all situations and deal accordingly. How many wars, how much suffering could be easily averted just by taking the advice of this short verse seriously.

Sentence pronunciation

Word pronunciation:

na
hi
verena
verāni
sammanti
idha
kudācanaṃ
averena
ca
esa
dhammo
sanantano