From The Oxford Companion to English Literature, ed. Margaret Drabble:
Samson Agonistes, a tragedy by *Milton, published 1671, in the same volume as *Paradise Regained. Its composition was traditionally assigned to 1666-70, but W. R. Parker in his biography (1968) argues that it was written much earlier, possibly as early as 1647. A closet drama never intended for the stage, it is modelled on Greek tragedy, and has been frequently compared to Prometheus Bound by *Aeschylus or Oedipus at Colonus by *Sophocles: other critics have claimed that its spirit is more Hebraic (or indeed Christian) than Hellenic. Proedominantly in blank verse, it also contains passages of great metrical freedom and originality, and some rhyme. Samson Agonistes (i.e. Samson the Wrestler, or Champion) deasl with the last phase of the life of the Samson of the Book of Judges when he is a prisoner of the Philistines and blind, a phase which many have compared to the assumed circumstances of the blind poet himself, after the collapse of the Commonwealth and his political hopes.
Samson, in prison at Gaza, is visited by friends of his tribe (the chorus) who comfort him; then by his old father Manoa, who holds out hopes of securing his release; then by his wife *Dalila, who seeks pardon and reconciliation, but by being repudiated shows herself 'a manifest Serpent'; then by Harapha, a strong man of Gath, who taunts Samson. He is finally summoned to provide amusement by feats of strength for the Philistines, who are celebrating a feast to *Dagon. He goes, and presently a messenger brings news of his final feat of strength in which he pulled down the pillars of the place where the assembly was gathered, destroying himself as well as the entire throng. The tragedy, which has many passages questioning divine providence ('Just or unjust, alike seem miserable'), ends with the chorus's conclusion that despite human doubts, all is for the best in the 'unsearchable dispose/ Of highest wisdom': its last words, 'calm of mind all passion spent', strike a note of Aristotelian *catharsis, and the whole piece conforms to the *neo-classical doctrine of unities.