Adam Clarke on Psalms 119:33

Teach me, O Lord, the way of thy statutes - To understand the spiritual reference of all the statutes, etc, under the law, required a teaching which could only come from God.

I shall keep it unto the end - Here is a good thing asked for a good end. He wishes for heavenly teaching; not to make a parade of it, but to enable him to discern his duty, that he might act accordingly.