The steps of his strength - Even in his greatest prosperity he shall be in straits and difficulties.
His own counsel - He shall be the dupe and the victim of his own airy, ambitious, and impious schemes.
The steps of his strength - Strong steps. “Steps of strength” is a Hebraism, to denote firm or vigorous steps.
Shall be straitened - Shall be compressed, embarrassed, hindered. Instead of walking freely and at large, he shall be compressed and limited in his goings. “Large steps,” “free movement,” etc. are proverbial expressions among the Arabs, to denote freedom, prosperity, etc. RosenmulIer. Schultens quotes the following illustrations from the Arabic poets. From Ibn Doreid, “He who does not confine himself within human limits, his vast strides shall be straitened.” And from Taurizius,” After the battle of Bedrense, the steps were straitened.” The meaning here is, that he would be greatly impeded in his movements, instead of going forth at large and in full vigor as he had formerly done.
And his own counsel - His own plans shall be the means of his fall.