B.G 5.02
śrī bhagavānuvāca
saṁnyāsaḥ karmaYōgaśca niḥśreyasakarāvubhau। tayostu karmasaṁnyāsāt karmayogo viśiṣyate ॥2॥
The revered Lord Said:
Definitve good results from both Yōga-of-action and Yōga-of-renunciation. But, between the action and renunciation, the Yōga-of-action is special.
Gīta Bhāshya 5.02
The word 'saṁnyāsa' in the current context refers to dispassion. It does not refer to monkhood.
nāyaṁ saṁnyāso yatyāśramaḥ -
The word 'sanyasa', i.e. renunciation in the current context, does not mean monkhood, the fourth order of life.
"dvandvatyāgāt tu saṁnyāsāt matpūjaiva garīyasī॥
iti vacanāt।
"Worship of Me is superior compared to giving up dualities because of renunciation."
- states a proverb.
"tāni vā etānyavarāṇi tapāṁsi nyāsa evātyarecayat।"
iti ca।
"He indeed advocated giving up of these lower forms of austerities."
-stated thus as well.
"saṁnyāsastu turīyo yo niṣkriyākhyaḥ sadharmakaḥ। na tasmāduttamo dharmo loke kaścana vidyate॥ tadbhaktopi hi yadgacchet tadgr̥hastho na dhārmikaḥ। madbhaktiśca viraktistadadhikāro nigadyate। yadā'dhikāro bhavati brahmacāryapi pravrajet॥"
iti nāradīye।
"Indeed, the fourth state, (turīya, i.e. beyond sleep, dream, and awake) which is identified with non-activity, has its own virtues. In the world, no other superior duty (dharma) comes to light compared to it. Even the householder, who is the follower of dharma, cannot go there, where the devotee goes. Dispassion is described as the eligibility to become my devotee. When a person becomes eligible, even a celibate student can take up monkhood."
-states Naradiya Purana.
"brahmacaryādeva pravrajet। yadahareva virajet॥"
iti ca।
"Even from the celibate student phase, one can take up monkhood, just like the day that illuminates immediately."
-stated thus as well.
"saṁnyāse tu turīye vai prītirmama garīyasī। yeṣāmatrādhikāro na teṣāṁ karmeti niścayaḥ॥"
ityādeśca brāhme।
"Indeed, my affection towards monastic order is greater. Certainly there is no need to engage in worldly actions for those who are eligible for the fourth order (i.e. monkhood)."
- so commanded in the Brahmanda Purana.
ato nātra āśramaḥ saṁnyāsa uktaḥ ॥2॥
Therefore, in this context, the fourth order of life, the monkhood, is not referenced.