In what way do men grieve the Spirit of God? The Apostle, having exhorted us not to grieve the Spirit of God, goes on to explain what grieves this Spirit: all bitterness and wrath, and anger and clamour, and blasphemy (cursing) and all malice. Let it all be put away from you, says the Apostle. In brief, the Spirit of God is grieved by our every sin. Let every sin be put away from us, and the Spirit of God will be filled with joy, and we shall rejoice in Him. When we have an important guest in the house, we do our utmost to give him pleasure. And yet, can there be a greater guest than the Spirit of God? And, since He is our most important and our most desired guest, we must make the greatest efforts to please Him. And we know what pleases the Spirit of God–the very same thing that pleases Christ the Lord. The Lord has said: ‘If you love Me keep My commandments.’ He who keeps Christ’s commandments, therefore, has love for the Son, keeping His command merits, and pleases the Father and the Holy Spirit also. The Apostle especially commends meekness, mercy and forgiveness. If we are meek, if we are merciful, if we forgive one another, than we shall please the Spirit of God that dwells in our hearts And the Spirit of God will then rejoice in us, and our whole being will vibrate with ineffable joy. 

Bishop Nikolai Velimirovich, The Prologue from Ochrid.