Love of Righteousness

Now this Scriptural instruction of which we speak has two main aspects. The first is that the love of righteousness, to which we are otherwise not at all inclined by nature, may be instilled and established in our hearts; the second, that a rule be set forth for us that does not let us wander about in our zeal for righteousness.
John Calvin - Institutes of The Christian Religion: 3.6.2

I do not insist that the moral life of a Christian man breathe nothing but the very gospel, yet this ought to be desired, and we must strive toward it. But I do not so strictly demand evangelical perfection that I would not acknowledge as a Christian one who has not yet attained it. For thus all would be excluded from the church, since no one is found who is not far removed from it, while many have advanced a little toward it whom it would nevertheless be unjust to cast away.
John Calvin - Institutes of The Christian Religion: 3.6.5

Calvin is talking here of righteousness, being acceptable in the eyes of God. He is not talking about self-righteousness, which is being smug and acceptable only to yourself. Calvin is also not calling for perfection, he is calling for a love of God and the righteousness of God:

⁷For the LORD is righteous, He loves righteousness;
The upright will behold His face.
Psalm 11:7 (NASB)

The call to righteousness is because of His love for it and for us. It is in His never changing character to be righteous, one of His attributes:

²⁴"But let justice roll down like waters
And righteousness like an ever-flowing stream.
Amos 5:24 (NASB)

We are called to it because He is holy and just and righteous. Love righteousness but know you will never perfect it, seek righteousness but know you will never have it fully embrace you in this world. For you and I are works in progess in this world:

⁶For I am confident of this very thing, that He who began a good work in you will perfect it until ^(A)the day of Christ Jesus.
Philippians 1:6 (NASB)