“If a strict accounting were made of what one owes God for the kindness He has bestowed upon him, no man would ever attain the reward of the Word-to-Come for his deeds, except by God’s grace toward him.  Therefore, do not rely on your deeds!   David said in this regard: ‘Grace, O God, is Yours; You reward a man according to his work.’  (Tehillim 62;13).”  ~ Chovos Halevavos