Why do we gather weekly at church? We, sinners, need Christ's forgiveness. As Christians, we follow Christ not because of His moral teachings but because He died for our sin. The readings are rife with forgiveness; indeed, it is the heart and soul of our faith.
From the Old Testament reading...David, after being convicted of adultery, and confessing it, is forgiven. It was really a series of sins: (1) He abdicated his kingly responsibility by staying home when his obligation was to go to battle; (2) Idly walking with this new-found time, he saw Bathsheba bathing and indulged his lust, finding out first that she was married; (3) He committed adultery anyway; (4) Upon Uriah's return, David got him drunk and sent him right back; (5) David arranged for Uriah's demise, involving Joab and the entire Israelite army in his sin. Nathan's story convicted David by the word of his own mouth; he repented and was forgiven. God restored even this despicable sinner! What love is this!
From the other readings...Peter denied Christ thrice - and was forgiven. Paul persecuted Christians from Jerusalem to Damascus - and was forgiven and transformed in a very dramatic way. Search a little farther yourself for other examples.
Are you less sinful? Not at all. Each of you has sinned against God - who forgives you when you repent. This is central and constant to our faith. Take advantage of the love of Jesus, your heart and soul!
Soli Deo gloria.