Hebrews 3:8

μὴ σκληρύνητε, the prohibitory subjunctive, v. Burton, p. 162. “The figure is from the stiffening by cold or disease, of what ought to be supple and pliable” (Vaughan). [The verb occurs first in Hippocrates, cf. Anz. 342.] It is ascribed to τὸν τράχηλον (Deuteronomy 10:16), τὸν νῶτον (2 Kings 17:14), τὴν καρδίαν (Exodus 4:21), τὸ πνεῦμα (Deuteronomy 2:30). Sometimes the hardening is referred to the man, sometimes it is God who inflicts the hardening as a punishment. Here the possible hardening is spoken of as if the human subject could prevent it. τὰς καρδίας, the whole inner man. ὡς ἐν τῷ … ἐρήμῳ. This stands in the psalm as the translation of the Hebrew which might be rendered: [“Harden not your hearts] as at Meribah, as on the day of Massah in the wilderness,” Meribah being represented by παραπικρασμός and Massah by πειρασμός. The tempting of God by Israel in the wilderness is recorded in Exodus 17:1-7, where the place is called “Massah and Meribah”. This occurred in the first year of the wanderings. παραπικρασμός is found only in this psalm (although παραπικραίνειν is frequent) its place being taken by λοιδόρησις in Exodus 17:7 and by ἀντιλογία in Numbers 20:12. It means “embitterment,” “exacerbation,” “exasperation”, κατὰ τὴν ἡμέραν is rendered by the Vulgate “secundum diem,” rightly. It means “after the manner of the day”. Westcott, however, prefers the temporal sense.