In the context of Nicholas' quote, do you think you're talking about the same kind of "looking in"?
I believe we are referring to the same introspection.
The statement by Bishop Beveridge is phenomenally biblical. The conclusion of Nicholas doesn't follow. Sinners undoubtedly have no righteousness of their own which can bear the scrutiny of the perfect law of God. It is certainly the case that the imputation of the righteousness of Christ is the only hope of sinners to find acceptance in the sight of God. But it is equally true that the righteousness of Christ is imputed to those that believe, and those only believe who have been regenerated by the Spirit of God. Where there are no marks of regeneration there is no reason to conclude that faith is genuine, and therefore no basis for claiming a saving interest in the finished work of Christ.
It's lamentable to see modern Christians suffering from psychological fracture. They try to produce religious experiences which bypass the heart with the result that they never feel true joy and peace in believing. Biblical doctrine needs to be presented in accord with the biblical view of man. The Bible does not speak of certain facts with which we must brainwash ourselves into the persuasion that all is well with us. The Bible speaks to the heart as the centre of man's religious and moral life, and by a complex balance of instruction, promise, and warning, it converts the soul through the gracious influence of the Spirit of truth.
Justification without regeneration would be a legal fiction -- which is a blatant contradiction to the epistemic claim of Scripture that the *truth* sets men free. Blessings!