“To the praise of the glory of his grace, wherein he hath made us accepted in the beloved.”  
Ephesians 1:6

He goes on to tell us the realities of those of us in the beloved:
“In whom we have redemption through his blood, the forgiveness of sins, according to the riches of his grace;”  Ephesians 1:7
In the beloved, we have redemption through his blood, the forgiveness of sins- in him, every mistake we might make is dealt with fervently and there is redemption; as though we never made such mistakes. He tells us this is according to the riches of his grace, meaning, that grace that he so lavished on us, that when men see at work in our lives, they would praise the glory of it, that grace also makes up for our mistakes- what should have been a life shattering mistake is upended by grace and results in the praise of his name!
“But if we walk in the light, as he is in the light, we have fellowship one with another, and the blood of Jesus Christ his Son cleanseth us from all sin.”  1 John 1:7
Our fellowship with God and his word cleanses us from all sin; he takes away the mistake and it’s effect from our lives, so much so that even when searched, such a mistake cannot be found and every consequence of that mistake is either nonexistent or a shining testimony of his goodness. Knowing that grace is made available to you even for the redemption of sins is the light of God’s word, walking in this light is fellowshipping with him and planting yourself in his tent of overflowing grace!