Isaiah 14:4 and 41:7 in LXX and Translation

Isaiah 14:4: καὶ λήμψῃ τὸν θρῆνον τοῦτον ἐπὶ τὸν βασιλέα Βαβυλῶνος καὶ ἐρεῖς ἐν τῇ ἡμέρᾳ ἐκείνῃ πῶς ἀναπέπαυται ὁ ἀπαιτῶν καὶ ἀναπέπαυται ὁ ἐπισπουδαστής

Brenton: "And thou shalt take up this lamentation against the king of Babylon, How has the extortioner ceased, and the taskmaster ceased!"

Knox: "it will be thy turn to have thy say against the king of Babylon. Can it be (thou wilt say) that the tyranny is over, the exactions at an end?"

Isaiah 41:7: ἴσχυσεν ἀνὴρ τέκτων καὶ χαλκεὺς τύπτων σφύρῃ ἅμα ἐλαύνων ποτὲ μὲν ἐρεῖ σύμβλημα καλόν ἐστιν ἰσχύρωσαν αὐτὰ ἐν ἥλοις θήσουσιν αὐτὰ καὶ οὐ κινηθήσονται

Brenton: "The artificer has become strong, and the coppersmith that smites with the hammer, and forges also: sometimes he will say, It is a piece well joined: they have fastened them with nails; they will fix them, and they shall not be moved."

NIV: "The metalworker encourages the goldsmith, and the one who smooths with the hammer spurs on the one who strikes the anvil. One says of the welding, 'It is good.' The other nails down the idol so it will not topple."

Gary V. Smith:

the prophet describes their deluded trust in idols made by skilled craftsmen, goldsmiths, and other workers (41:7).160 The builders of these idols say that the results of their effort to construct this man-made god are “good”, but Gen 1:12,31 indicates that only what God created was “good.” In order to show how precarious the strength of their faith in the idol was, the prophet explains that it all depends on the nail or peg that will keep the idol standing up securely on a pedestal.

See Smith, Gary V. The New American Commentary - Isaiah 40-66: 15B (Kindle Locations 3322-3326). B&H Publishing. Kindle Edition.