यदा वै करोत्यथ निस्तिष्ठति नाकृत्वानिस्तिष्ठति कृत्वैव निस्तिष्ठति कृतिस्त्वे-व विजिज्ञासितव्येति कृतिं भगवो वि-जिज्ञास इति ॥ १ ॥
In plain words
When a person acts, then stability is attained; nothing is accomplished without action, and only through action is stability reached. Yet action itself must be inquired into. 'Venerable sir, it is action that I wish to understand.'
Close to the Sanskrit
When indeed one acts, then one attains stability; without acting one does not attain stability; having acted indeed one attains stability. Action, however, must be inquired into. 'Action, venerable sir, I wish to know.'