And first, of His title to our love. Could any title be greater than this, that He gave Himself for us unworthy wretches? And being God, what better gift could He offer than Himself? Hence, if one seeks for God's claim upon our love here is the chiefest: Because He first loved us (I John 4.19).
Bernard of Clairvaux, 1190-1153, On Loving God, Chapter 1 (CCEL internet library, Posted by Paul Halsall (HALSALL@MURRAY.FORDHAM.EDU)).
Why is it important to love God? What are the reasons for doing so?