This is a great psalm because we see that we are directed back to the FATHER of Creation. King David asks the Creator to create in him a clean heart; this is a cry for repentance. King David understood that his heart was not right and that the only way he could have it right was to ask GOD into his heart. When we ask GOD to forgive us because we have come into the knowledge and acceptance that we are sinners and we acknowledge that JESUS is the SON of the True and Living GOD we turn away from wickedness and we consciously refuse to habitually practice wrong doing. We live in a time that King David did not and that is that we have grace. This is why King David pleaded with the LORD GOD that HE would not take away HIS presence; HIS Holy Spirit which did not reside within him but on him. We however; have a promise that the LORD GOD will never leave or forsake us. But you can feel as though you are alone; without HIS presence if you have made up in your mind that being saved gives you license to continue to live your life as you did before you accepted JESUS as your Savior. The LORD GOD restores daily to HIS children that everlasting joy of being saved. Also we are continually upheld in HIS right hand because of HIS Spirit. Though King David had assurance of his relationship with the LORD GOD we have assurance and the promise that the LORD GOD has cleansed our heart and has sent HIS Holy Spirit to remain within us and bring comfort to us by teaching us about JESUS and we have an everlasting joy that is not determined on how we feel but because of who our GOD is.