From today's reading (1 John 4:19-5:4)
'this is what loving God is –
keeping his commandments;'
In today's reading St John gives us a clear instruction in loving God. He tells us that loving God is achieved by keeping His Commandments.
Why not explore the Commandments today? Consider reading about the Ten Commandments in the Catechism here: http://www.vatican.va/archive/ccc_css/archive/catechism/command.htm
But what about the Sermon on the Mount when Jesus gives us a 'new' commandment to love one another as he has loved us? This, the Catechism states 'fulfils, refines, surpasses, and leads the Old Law to its perfection' (para 1967). Jesus' Commandment does not replace the Ten Commandments of the Old Testament; rather, Jesus' commandment completes them as it 'fulfils the divine promises by elevating and orienting them towards the 'Kingdom of Heaven'' (para 1967).
To read more on Jesus' commandment and its relationship with the Ten Commandments click here: http://www.vatican.va/archive/ccc_css/archive/catechism/p3s1c3a1.htm
Further, there are precepts of the Church (specific commandments of the Church) and these can be found from para 2042 onwards in the Catechism. They include commandments to attend Mass and attend confession. Click here to view the precepts: http://www.vatican.va/archive/ccc_css/archive/catechism/p3s1c3a3.htm