Adam Clarke on Acts 26:22

Having - obtained help of God - According to the gracious promise made to him: see Act 26:17.

Witnessing both to small and great - Preaching before kings, rulers, priests, and peasants; fearing no evil, though ever surrounded with evils; nor slackening in my duty, notwithstanding the opposition I have met with both from Jews and Gentiles. And these continual interpositions of God show me that I have not mistaken my call, and encourage me to go forward in my work.