Do you believe you love perfectly?
I don't.
It's all grace.
Again, we have three basic concepts going on here, all involving the absolute need for grace. Many Protestants believe that no righteousness is possible for man,
or that none is necessary in any case in order to be
justified, such that, according to some, sin/personal unrighteousness aren't a concern for a believer: grace covers it all.
Servant believes that personal righteousness, from Christ,
is required and apparently believes that grace causes a true believer to be totally changed and made perfect all at once-and that this
must be the case.
The church, historically, has taught that only God can turn man to Himself an justify man, by grace though faith, but that even then man can resist that gift of faith and say "no". But, having said "yes", he enters a state of justice defined first of all by union with God: he is justified and the righteousness of God is planted in him. He can continue to remain in God, picking up his cross and following as best he can whereupon God will cultivate in him even stronger and greater and more confirmed righteousness yet, defined primarily as love.
We continue to feed off of His grace, of His life in us, or not. Because we can still say "no" at any point along the way. The "way" is a
journey, that we must be on, and it’s a journey to
perfection, with trials and errors and challenges and slips and testing and, hopefully refining. As we stay the course we become more and more like God- and that’s man’s very purpose or telos. At the end of our lives we'll know with 100% certainty how we've done with what we’ve been given as the Just Judge renders
His determination.
We can have a strong level of assurance based on fruit in our lives, but yet a healthy, somewhat guarded assurance due to our limitations, weaknesses, and tendency to sin.
He’s wholly trustworthy and true while we’re the wildcard in it all. And He’s only seeking to draw us into greater and greater integrity, meaning greater and greater love for Himself and neighbor.
The church teaches that absolute perfect sinlessness is not possible for man in this life, but that growth in righteousness and away from sin, especially those sins that lead to death as they're directly opposed to and destroy love in us, is absolutely necessary. It's a journey, an incomparably good and worthy one, and one we must be on,
with God.