Verse 14

In plain words

Now tapas is taken up, and it is spoken of in three kinds —

Gods, and priests, and teachers, and the wise -- worship of all four of them; along with purity; uprightness, meaning simple straightforwardness; celibacy; and non-violence -- all of this is accomplished through the body, so it is called 'bodily' austerity, achieved by every one of the body's own instruments, its organs of action, together with the doer himself and the rest. That is what bodily austerity means. And indeed, it will be said later: 'these five are the causes behind any action' (Bhagavad Gita 18.15).

Close to the Sanskrit

Now, at this point, austerity is spoken of as threefold —

Gods, and twice-born, and teachers, and wise men -- 'gods-twiceborn-teachers-wise'; the worship of them -- 'the worship of gods, twice-born, teachers, and wise men'; purity; uprightness, i.e. straightforwardness; celibacy and non-violence -- to be accomplished by the body -- [this is called] 'bodily' [austerity]; accomplishable by all the instruments having the body as their chief, [that is,] the organs of action, and by the agent and so on -- [this] is called bodily austerity. For he will indeed say [later]: 'these five are the causes of that [action]' (Bhagavad Gita 18.15).

In plain words

“Now bodily tapas: taking part in works that help others; making the body holy through pūjā of the Paramātma, bhajana, pradakṣiṇa, āsana, brahmacarya and prāṇāyāma; serving the poor and the sick; making the body holy through conduct in keeping with good ways. One must use the body in good deeds such as these.”