Remember and be Fruitful
There is a positive correlation in a Christian’s life between his memory that he is forgiven of his sins, and the fruitfulness of his life. If you are in Christ, there will be a positive correlation in your life between your memory that you are forgiven of your sins, and the fruitfulness of your life.
In 2Peter 1, the Apostle Peter mentions godly qualities like self control, and brotherly affection, and steadfastness, and love (2Pe.1:5-8). And he says that if we lack these qualities, we will be ineffective and unfruitful in our knowledge of Jesus Christ. The reason he says we may lack these things is this: “whoever lacks these qualities... [has] forgotten that he was cleansed from his former sins.” So again, if you are in Christ, there will be a positive correlation in your life between your memory that you are forgiven of your sins, and the fruitfulness of your life.
Simply put, if we have any hope at all of living an effective and fruitful life in Christ - a life that really does succeed in advancing the kingdom of God - then we must remember that we have been forgiven of our former sins, as Peter says. In other words, we’ve got to remember the gospel!
Remember the good news that God is redeeming the world and his people through Jesus Christ. Remember that turning away from our sins, and turning to trust in Jesus Christ alone for the forgiveness of our sins, we are saved from the judgment of God; and we can rest fully at peace with him and his people forever.
And remember that remembering this will be a springboard into an effective and fruitful life in God's eyes.