Six at the top means:
If one is too severe in setting up restrictions, people will not endure them. The more consistent such severity, the worse it is, for in the long run a reaction is unavoidable. In the same way, the tormented body will rebel against excessive asceticism. On the other hand, although ruthless severity is not to be applied persistently and systematically, there may be times when it si the only means of safeguarding against guilt and remorse. In such situations ruthlessness toward oneself is the only means of saving one's soul, which otherwise would succumb to irresolution and temptation.