(Targum; Sifri; Ibn Ezra; Bachya). Tzur in Hebrew, usually denoting 'rock,' or 'bedrock.' The Septuagint simply translates it as 'God' (cf. Berakhoth 5b). Some see this as indicating that God is permanent like a rock (Ibn Ezra). Others see it denoting that God is the bedrock of our existence (Moreh Nevukhim 1:16). Others see the word tzur as coming from yatzar, 'to form,' denoting that God is the creator (Sifri). Or, from tzayar, 'to draw,' that He is the divine artist (Berakhoth 10a). Or, from tzarar, 'to bind together,' indicating that He is the unifying force in the universe, and the one to whom all are bound (HaKethav VeHaKabbalah).
Or, 'true Omnipotent One' (Ibn Ezra).
(Ralbag; Malbim; HaKethav VeHaKabbalah). Literally, 'Destruction to Him not His children their defect.' Or, 'They have hurt themselves, not Him, faulted children' (Targum); 'The defect of His non-children is that they have been corrupt to Him' (Ibn Ezra; Ramban; Sforno); 'They were corrupt to Him, not [like] children; this is the defect of the warped and twisted generation' (Saadia; cf. Lekach Tov); 'They have been corrupt, not Him, it is His children's defect' (Ralbag); 'The ones who have corrupted His [name] are not His children because of their defect' (Abarbanel); 'Is destruction His? No! It is the fault of His children' (Moreh Nevukhim 3:12; Chizzkuni); 'Have they corrupted Him? No. It is [merely] their own defect' (Abarbanel); 'He destroyed His non-children, but it was their own fault' (Chizzkuni); 'Their defect has corrupted it so that they are no longer His children' (Hirsch); or, 'They were corrupt, not [pleasing] Him, defective children' (Septuagint).
Or, 'a warped.'