I love this quote. Sherlock is saying that while he helps with good deeds he is far from good. But i disagree by spending more time around john Sherlock is slowly becoming the the good man he was thought to be.
I loved this quote the moment I heard it. 30 Best Sherlock Quotes from 'The Six Thatchers' - Sherlock Holmes: Intuitions are not to be ignored, John. They represent data processed too fast for the conscious mind to comprehend.