[When they had apprehended him, etc.] Question: How did the Philistine lying in wait know that Samson had actually lost his strength? Responses: 1. Because on this occasion they certainly persuaded themselves that Samson had confessed the truth (Tostatus). But why were they not fearing that Samson had lied as always hitherto? And why was it necessary to wake Samson up? or why did they not fall upon Samson while he was sleeping, if they knew that for certain? 2. It appears that it is to be altogether affirmed that also on this occasion bonds were used (even if Scripture keeps silent about that fact); when it was ascertained that he was not able to break them, then the harlot with a signal given urged the Philistines to spring out of their hiding-places (Bonfrerius). [If you should say that it is said that he was bound afterwards, it is able to be responded that Samson was bound by Delilah with cords, as if to make trial, but he was bound afterwards by the Philistines more securely, and with chains.]
The Philistines now durst apprehend him, because they rested in the assurance which Delilah had given them, that now all was discovered and done.
[They dug out his eyes] So that, if his strength should return to him, they might render that useless to him, since he sees not whom he would strike. He is justly and by a fitting punishment deprived of his eyes, because by them he had lustfully gazed upon Delilah. Nevertheless, this punishment was salutary for him; for by this blindness the eyes of his mind were opened, so that by his punishment he might acknowledge his fault, and, being penitent concerning it, call upon God, and so, falling upon His grace before Him, might receive his strength from Him (Lapide).
Put out his eyes; which was done by them out of revenge and policy, to disenable him from doing them much harm, in case he should recover his strength; but not without God’s providence, punishing him in that part which had been greatly instrumental to his sinful lusts.
[They brought him bound with chains, בַּנְחֻשְׁתַּיִם] In shackles, or, chains (Septuagint, Jonathan, Syriac, Arabic, Munster, Tigurinus), either of iron (Vatablus, Jonathan), or of copper (Munster, Tigurinus, Drusius), or of steel (Junius and Tremellius, Bochart’s Sacred Catalogue of Animals). The word נְחשֶׁת signifies both copper, as commonly; and steel, as in this place and in Lamentations 3:7, whence it is that the Hebrews interpret נָחוּשׁ as steel, Leviticus 26:19; Job 6:12; Isaiah 48:4 (Bochart’s Sacred Geography “Phaleg” 3:12:207).
Brought him down to Gaza, because this was a great and strong city, where he would be kept safely; and upon the sea-coast, at sufficient distance from Samson’s people; and to repair the honour of that place, upon which he had fastened so great a scorn, verse 3. God also ordering things thus, that where he first sinned, verse 1, there he should receive his punishment.
[In the prison, בְּבֵ֥ית הָאֲסִירִֽים׃] In the house of those bound: Thus the Hebrews call prison (Vatablus). Mills that are moved by the flowing of water or the impulse of the winds are the invention of a later age: those ancients were want to make use of push-mills, which were turned by mules or slaves; among the number of which slaves was Samson (Bonfrerius). Hence it appears that in the prison were millstones, whereby the prisoners were preparing food (Drusius); lest they, being idle, should eat bread (Vatablus). He here calls a mill a prison, as in Exodus 12:29. Now, the eyes were wont to be taken from those condemned to the mill, lest dizziness should hinder labor: for which cause Herodotus in “Melpomene” narrates that that the eyes were taken from slaves that are involved in the preparation of milk, and that go round the vessel in which there was milk (Grotius). Moreover, it belonged to the most abject (and grievous [Malvenda]) servitude in prison to grind (Drusius). See Exodus 11:5; Matthew 24:40; Juvenal’s Satires 8, …offspring worthy only of turning the millstone (Malvenda).
He did grind in the prison-house, as captives and slaves use to do: see Exodus 11:5; Isaiah 47:2; Matthew 24:41. He made himself a slave to vile lusts and harlots, and now God suffers men to use him like a slave.
 Hebrew: וַיֹּאחֲז֣וּהוּ פְלִשְׁתִּ֔ים וַֽיְנַקְּר֖וּ אֶת־עֵינָ֑יו וַיּוֹרִ֙ידוּ אוֹת֜וֹ עַזָּ֗תָה וַיַּאַסְר֙וּהוּ֙ בַּֽנְחֻשְׁתַּ֔יִם וַיְהִ֥י טוֹחֵ֖ן בְּבֵ֥ית הָאֲסִירִֽים׃
 Hebrew: וַיְנַקְּרוּ.
 נְחשֶׁת signifies copper.
 Lamentations 3:7: “He hath hedged me about, that I cannot get out: he hath made my chain (נְחָשְׁתִּי) heavy.”
 Leviticus 26:19: “And I will break the pride of your power; and I will make your heaven as iron, and your earth as brass (כַּנְּחֻשָׁה)…”
 Job 6:12: “Is my strength the strength of stones? or is my flesh of brass (נָחוּשׁ)?”
 Isaiah 48:4: “Because I knew that thou art obstinate, and thy neck is an iron sinew, and thy brow brass (נְחוּשָׁה)…”
 Exodus 12:29: “And it came to pass, that at midnight the Lord smote all the firstborn in the land of Egypt, from the firstborn of Pharaoh that sat on his throne unto the firstborn of the captive that was in the dungeon (בְּבֵ֣ית הַבּ֑וֹר, the house of the pit or cistern); and all the firstborn of cattle.”
 Histories 4:2.