"Remember O LORD, Your compassion and Your lovingkindnesses, For they have been from of old. Do not remember the sins of my youth or my transgressions; According to Your lovingkindness remember me, For Your goodness' sake, O LORD. Good and upright is the LORD; Therefore, He instructs sinners in the way," (Psalm 25:6--8).
Ever been in a meeting where you were able to listen to a really godly believer pour out his or her heart to the Lord? It can be a worship service in itself. Such a one seems to draw us all into the very presence of the King, filling us with a greater wonder and awe that He should love such unworthies so graciously.
Passages such as this are like that... we have the privilege of eavesdropping as David pours out his heart to the God of grace, to pardon him according to His infinite goodness. He is not here worried that the omniscient God could actually forget something... rather, David is pleading pardon by highlighting God's attributes of compassion, lovingkindness, and goodness. God loves for His children to pray His character as a basis for their requests, to pray His Word to Him in praise and supplication, reveling in His uprightness.
Do we pray Scripture to the Lord? Have we paid the price of memorizing His Word, thereby incorporating it into our praying? Do we rejoice in His character, every attribute? May we praise, plea, and petition in a manner worthy of our good God.