When followers of the Outer Tantra practice in retreat, they are very particular about personal hygiene, keeping a vegetarian diet, and washing themselves three times a day; the focus is on one’s conduct, and they do very well in this respect, but less so in the practice. Actually, the more one is fixated on the particulars of behavior, the more likely problems in practice will surface. The higher the state one reaches in practice, the more likely some improprieties may appear in one’s conduct. Naturally, impropriety does not mean wrongdoings such as killing, stealing, lying and so on are casually tolerated. You can get a better understanding of this from the life stories of the eighty great siddhas of ancient India. 

~Depicted from GATEWAY TO VAJRAYANA PATH - The Parable of a Black Snake