Yoga sutra 2.31
jāti-deśa-kāla-samaya-anavacchinnāḥ sārva-bhaumāḥ mahā-vratam
When the five principles mentioned in the previous sūtra are not limited by conditions - situation, place, period and circumstances – this is called the “great observance”
In this sūtra Patanjali says that if you are able to practice the five yamas without compromise/regardless of who you are, the location you are in, the time it is or the circumstances that exist, you are practising the “great observance”.
In practice, ethical rules cannot be observed unfailingly. For example, there may come a need for violence in self-defence. You therefore ought to set yourself realistic goals, taking into account the circumstances you find yourself in.
Damian Cadman-Jones is an authorised teacher of Prana Vashya Yoga™