In English the lyrics of the madrigal mean something like:

Damon e Filli

Damon e Filli insieme
Guerreggiavan frà lor con forz' estreme
Parieran l'armi i colpi e le ferite
Et era Amor present' à si gran' lite.

Eran guardi possenti
Le lor armi c'havean salde e pungenti
Eran sospiri i colpi, e i cari baci
Erano le ferite accorte, e audaci.

Ma si cangiò la sorte
Che da colpo mortal sentendo morte
Filli nel petto; cede, e s'abbandona
Dicendo amico io ti perdon, perdona.

Non sia mai che tu pera
All'hor disse Damon dolce Guerriera
Questa che ti par morte, è dolce vita
Ch'à guerregiar spesso gl'Amanti invita.
 
Damon and Phyllis were locked in combat,
holding nothing back.
Their weapons were equal, as were the blows and wounds exchanged,
and the god of love was there to witness such a great struggle.

Potent glances were their weapons,
sturdy and piercing,
sighs were their blows, and tender kisses
were the wounds they boldly inflicted.

But fate changed,
which deals mortal blows; Phyllis, feeling death
in her breast, yielded and gave herself up,
Saying, 'Friend, I forgive you; pray forgive me.

May you never perish.'
Then Damon replied: 'Sweet warrior,
what you take to be death is really sweet life,
which often moves lovers to engage in combat.'