Mahabharata 3.33.44

3.33.44

pṛthivīṃ lāṅgalenaiva bhittvā bījaṃ vapatyuta |
āste'tha karṣakastūṣṇīṃ parjanyastatra kāraṇam || 44 ||

Having exerted thyself thou wilt know what the fruit of thy exertion will be. The tiller tilleth with the plough the soil and soweth the seeds thereon. He then sitteth silent, for the clouds (after that) are the cause that would help the seeds to grow into plants. If however, the clouds favour him not, the tiller is absolved from all blame. He sayeth unto himself, 'What others do, I have done. If, notwithstanding this, I meet with failure, no blame can attach to me.' Thinking so, he containeth himself and never indulgeth in self-reproach. O Bharata, no one should despair saying, 'Oh, I am acting, yet success is not mine! For there are two other causes, besides exertion, towards success. Whether there be success or failure, there should be no despair, for success in acts dependeth upon the union; of many circumstances. If one important element is wanting, success doth not become commensurate, or doth not come at all. If however, no exertion is made, there can be no success. Nor is there anything to applaud in the absence of all exertion. The intelligent, aided by their intelligence, and according to their full might bring place, time, means, auspicious rites, for the acquisition of prosperity. With carefulness and vigilance should one set himself to work, his chief guide being his prowess. In the union of qualities necessary for success in work, prowess seemeth to be the chief.