तस्माच्छास्त्रं प्रमाणं ते कार्याकार्यव्यवस्थितौ।ज्ञात्वा शास्त्रविधानोक्तं कर्म कर्तुमिहार्हसि
tasmāch chhāstraṁ pramāṇaṁ te kāryākārya-vyavasthitau jñātvā śhāstra-vidhānoktaṁ karma kartum ihārhasi
Therefore, whenever there is doubt as to whether you should do something or not, let the scriptures guide your conduct. In the light of the scriptures, you should labor your whole life.
Translated by Shri Purohit Swami
Therefore, let the scripture be thy authority in determining what ought to be done and what ought not to be done. Having known what is said in the ordinance of the scriptures, thou shouldst act in this world.
Translated by Swami Sivananda
Word meanings (from the gita/gita dataset)
tasmāt—therefore; śhāstram—scriptures; pramāṇam—authority; te—your; kārya—duty; akārya—forbidden action; vyavasthitau—in determining; jñātvā—having understood; śhāstra—scriptures; vidhāna—injunctions; uktam—as revealed; karma—actions; kartum—perform; iha—in this world; arhasi—you should