He hath said in his heart - The phrase, “he hath said,” means that this was his deliberate and settled character. What is here described was no sudden thing. It was not the freak of passion; it was a deliberately-formed purpose. The phrase, “in his heart,” means that he had purposed this; he had said this to himself in a spirit of self-gratulation and confidence.
I shall not be moved - That is, he was confident in his present condition, and he apprehended no changes. He had formed his plans so wisely, that he believed he had nothing to apprehend; he feared neither sickness nor adversity; he dreaded not the power of his enemies; he feared nothing even from the providence of God; he supposed that he had laid the foundation for permanent prosperity. This feeling of self-confidence and of security is sometimes found, to an extent that cannot be justified, in the hearts of even good people (compare the note at Job 29:18); and it is common among the wicked. See Psalms 49:11; Job 21:9.
For I shall never be in adversity - Margin, “unto generation and generation.” The margin expresses the correct sense. The idea of the wicked, as expressed here, is that they and their families would continue to be prosperous; that a permanent foundation was laid for honor and success, and for transmitting accumulated wealth and honors down to far distant times. It is a common feeling among wicked men that they can make permanent their titles, and possessions, and rank, and that nothing will occur to reduce them to the humble condition of others. Nothing more cleverly shows the pride and atheism of the heart than this; and in nothing are the anticipations and plans of human beings more signally disappointed. Compare the case of Shebna; see the note at Isaiah 22:15 ff.