Lead me, O Lord, in thy righteousness. Here at last we find what David prayed for. Previously, we have only heard him entreat that his prayer may be heard (Psalms 5:1, Psalms 5:2), declare that he will pray early (Psalms 5:3), and before the tabernacle (Psalms 5:7); now we learn what his prayer is.
It is that God will lead him in the path of his righteousness—that righteousness of which he is the pattern, and whereof he approves; and will "make his way plain for him," i.e. show it him clearly, so that he cannot mistake it.
God is asked to do this, especially because of David's enemies, or of "those that lie in wait for him", lest, if he were to make a false step, they should triumph over him, and so he should bring discredit upon the cause of God and of his saints.
Make thy way straight (plain, Revised Version) before my face. Not so much "smooth my way," or "make it level" or "easy," as "put it plainly before me" (scrap. Psalms 25:5; and Psalms 27:11, '"Teach me thy way, O Lord, and lead me in a plain path, because of mine enemies").