My Musings – Lest we think that being more righteous than most, or that our “righteous” acts will outweigh the rest, and will be sufficient to gain us entry to Heaven, this verse assures us that these will not save us. It is not because of our righteousness, it is in spite of our unrighteousness. If not for God’s mercy, there would be no salvation for anyone. Furthermore, mercy is not an obligation (as if we earned it), it is wholly unmerited, and undeserving.
My Advice – Seek His mercy, because you cannot achieve salvation any other way.