1 Peter 4:8 And above all things have fervent love among yourselves: for love shall cover the multitude of sins.

How can love cover a multitude of sins?

We need to understand the nature of love.  Most importantly, that God is love.  We could say that God covers a multitude of sin.  1 John 4:16 And we have known and believed the love that God has toward us. God is love; and he who dwells in love dwells in God, and God in him. *  17 By this our love is made complete, that we may have boldness in the day of judgment: because as He is, so are we in this world.  18 There is no fear in love; but complete mature love casts out fear: because fear has torment. He who fears is not made complete in love.

Romans 14:23 tells us simply that anything that is not of faith is sin. Faith comes from God. (James 1:17) Faith comes by hearing the utterance of God. (Romans 10:17)  Did you ever realize just how narrow that narrow way is?  If God didn't ask you to do it and you do, then that is sin.  God wants to be part of our every thought, word, and deed.  He designed us for this.  This is the only way that we can find our fulfillment.  All else is sin.  There are several types of sin, but they all come down to this.

Romans 13:8-10 Owe no man any thing, but to love one another: for he that loveth another hath fulfilled the law.  For this, Thou shalt not commit adultery, Thou shalt not kill, Thou shalt not steal, Thou shalt not bear false witness, Thou shalt not covet; and if there be any other commandment, it is briefly comprehended in this saying, namely, Thou shalt love thy neighbour as thyself.  Love worketh no ill to his neighbor: therefore love is the fulfilling of the law.

There is no obedience to the law without love.  There is no love without obedience to the law.  Yet, we are incapable of good works.  We are incapable, in our natural state, of love.  We need the Holy Spirit flowing through us and doing His works through us.  God is love.

Righteousness is the opposite of sin.  Righteousness is love.

Here's how it works: God speaks His vision of hope to us. We hear. We receive God's Word, His Utterance, and believe Him. Faith comes by hearing the Word (utterance) of God. Faith, then, gives us access to grace. Jesus stands at the door knocking and faith allows us to open that door. When we open that door, grace flows in with all the glory of God, and it brings God's free gift of righteousness with it. We yield ourselves to that righteousness, God does His works through us. This is doing the right things right. It is the only way we can do anything right.

(some caveats about hearing God's Voice)

This is the righteousness that is by grace through faith.

The words of which God speaks are real.  They are Truth.  It is His Truth that sets you free from Satan's lies.  He who does righteousness is righteous. (1John 3:7) Real righteousness is by grace through faith. God's process for righteousness is by grace, and grace is through faith. (Eph 2:8-10)