3.23

यदि ह्यहं न वर्तेयं जातु कर्मण्यतन्द्रितः ।
मम वर्त्मानुवर्तन्ते मनुष्याः पार्थ सर्वशः ॥

yadi hy ahaṃ na varteyaṃ jātu karmaṇy atandritaḥ
mama vartmānuvartante manuṣyāḥ pārtha sarvaśaḥ

śrībhagavān (श्रीभगवान्) is speaking, and yadi (यदि) opens the consequence of the stopping he has just refused.

The verse

If I did not stay engaged in action, tireless, at any time, humans would follow my path in every way, Pārtha (पार्थ).

नेपालीमा

यदि म कहिल्यै नथाकी कर्ममा लागेर नबसेँ भने, हे पार्थ, मानिसहरू सबै प्रकारले मेरो बाटो पछ्याउँथे।

Where it sits

3.21 was the general rule, and this is the same rule with his own path as the measure. The ruin that would follow the copying is the next verse, still under yadi (यदि).

Split: यदि + हि + अहम् + न + वर्तेयम् + जातु + कर्मणि + अतन्द्रितः + मम + वर्त्म + अनुवर्तन्ते + मनुष्याः + पार्थ + सर्वशः

yadi + hi + aham + na + varteyam + jātu + karmaṇi + atandritaḥ + mama + vartma + anuvartante + manuṣyāḥ + pārtha + sarvaśaḥ

Sanskrit, in depth

The words

देवनागरीWordGrammarSense
यदिyadiindeclinableif.
हिhiindeclinablefor.
अहम्ahamnominativeI.
नnaindeclinablenot.
वर्तेयम्varteyamoptative, 1st singular of vṛt (वृत्)I would engage.
जातुjātuindeclinableat any time, ever.
कर्मणिkarmaṇilocativein action.
अतन्द्रितःatandritaḥnominativeunwearying, not lazy.
ममmamagenitivemy.
वर्त्मvartmaaccusative of vartman (वर्त्मन्)path.
अनुवर्तन्तेanuvartantepresent, 3rd plural, middlethey follow.
मनुष्याःmanuṣyāḥnominative pluralhumans.
पार्थpārthavocativePārtha (पार्थ).
सर्वशःsarvaśaḥindeclinablewholly, in every way.

The phrases

यदि हि अहम् न वर्तेयम् जातु कर्मणि अतन्द्रितः yadi hy aham na varteyaṃ jātu karmaṇi atandritaḥ is the condition. If I did not, at any time, stay engaged in action without weariness. हि + अहम् hi + aham is hy aham (ह्यहम्). कर्मणि + अतन्द्रितः karmaṇi + atandritaḥ is karmaṇy atandritaḥ (कर्मण्यतन्द्रितः).

mama vartma anuvartante manuṣyāḥ pārtha sarvaśaḥ (मम वर्त्म अनुवर्तन्ते मनुष्याः पार्थ सर्वशः) is what people would do with the gap. Humans follow my path in every way. वर्त्म + अनुवर्तन्ते vartma + anuvartante is vartmānuvartante (वर्त्मानुवर्तन्ते).

Sanskrit in this line

varteyam (वर्तेयम्) is the optative, "I would engage," inside yadi (यदि). The indicative varte (वर्ते) in 3.22 was "I do engage." The optative is the action that is not happening. Do not recite them as the same word. The yadi (यदि) needs the optative.

Say it back

The if, and who follows. If atandritaḥ (अतन्द्रितः) drops, he might be refusing the work. The verse says he does it without slack.