To enter God’s presence, we need to be holy, set apart to Him.  But we have all sinned and fall short of His glory.  We must be cleansed of our sin, guilt, and shame.  Nothing we can do can give us clean hands and clean hearts.  But Jesus took our sins upon Himself and died in our place.  His blood purifies us from all sin when we turn to Him from self and sin and put our faith in His death and resurrection, in His love for us.