1 Peter 4:8

"Above all, love each other deeply, because love covers over a multitude of sins." NIV translation

When asked about the greatest commandment, Jesus said that the first was to love God and the second was to love others (see Matthew 22:34-40). Jesus demonstrated this love when He went to the cross for our sins and that is what it is talking about covering over sins. Our love for Jesus, which is due to the fact that He loved us first, enables us to love others and is a sign that we are saved.

1 Peter 4:9 & 10

"Offer hospitality to one another without grumbling. Each one should use whatever gift he has received to serve others, faithfully administering God's grace in its various forms." NIV translation

In verse 8, we were told to love each other and here we see that love is practical and has a purpose. It is practical in that it is given, with a joyful heart, to others to help to meet a need.

The purpose is so that we can show God's grace to build up others and let them know about our Lord Jesus Christ. God has prepared these things for us to do (Ephesians 2:10) and so we just have to learn to listen to the prompting of the Spirit and to use our gifts as directed.