Judge me, O YHWH, for I have walked in my integrity,
I have trusted also in YHWH without wavering.
He is confident that having received the forgiveness that he had pleaded for in Psalms 25 he can now call on YHWH to judge him in the present as one who has been faithful, and has walked in integrity (compare Psalms 25:21). He is ready to open his whole life to YHWH's scrutiny. And he is not afraid, because he knows that he has trusted YHWH with an unwavering trust (compare Psalms 25:2), a trust that does not slide about in constant changeableness, ‘none of his steps will slide' (Psalms 37:31). He has turned neither to left nor right (compare Isaiah 30:21). In all this he wants YHWH to shine His light on him so that he may ‘walk in the light' before Him (compare 1 John 1:7).
The request to be judged is also a prayer that God will stand on his side against his adversaries (Psalms 43:1). He is aware that unless YHWH is satisfied with what he is he has no right to such protection and help.