Lutherans believe that God offers his eternal love to humans as a gift - it is not something that they can earn by what they do. 

In Christ Jesus, God has shown us that he accepts us as we are, with our many failings.  In believing that alone, we are put right with God.  Lutherans sum this up by professing that we are 'justified by grace, through faith'. “For God so loved the world that he gave his only Son, so that everyone who believes in him may not perish but may have eternal life. (John 3:16) Such faith empowers people to express love to their neighbours freely - not in an effort to win God's salvation, but in praise of the God who loves us unconditionally and eternally. Lutherans believe in the Holy Trinity, one God - Father, Son and Holy Spirit.