Charles Ellicott Commentary Isaiah 30:12

"Wherefore thus saith the Holy One of Israel, Because ye despise this word, and trust in oppression and perverseness, and rely thereon;" — Isaiah 30:12 (ASV)

Because ye despise this word —that is, the message which Isaiah had delivered against the alliance with Egypt. We note how the prophet enforces it, as coming from that very Holy One of Israel of whom they were tired of hearing.