Charles Ellicott Commentary Isaiah 30:13

"therefore this iniquity shall be to you as a breach ready to fall, swelling out in a high wall, whose breaking cometh suddenly in an instant." — Isaiah 30:13 (ASV)

As a breach ready to fall. —The ill-built, half-decayed houses of Jerusalem may have furnished the outward imagery of the parable. First comes the threatening bulge, then the crack, and then the crash. That was to be the outcome of the plans they were building up on the unsound foundation of corrupt intrigue. In Ezekiel 13:10 we have the additional feature of the untempered mortar with which such a wall is built.