On verses, from major Hindu texts, similar in purport to those found in the Bhagawat Gita
Bhagavata Purana talks about following one's own Dharma in SB 3.28.2.
vidharmāc ca nivartanam
daivāl labdhena santoṣa
One should execute his prescribed duties to the best of his ability and avoid performing duties not allotted to him. One should be satisfied with as much gain as he achieves by the grace of the Lord, and one should worship the lotus feet of a spiritual master.
Also, Nishkama Karma is described in SB 11.3.46.
vedoktam eva kurvāṇo
niḥsaṅgo ’rpitam īśvare
naiṣkarmyaṁ labhate siddhiṁ
By executing without attachment the regulated activities prescribed in the Vedas, offering the results of such work to the Supreme Lord, one attains the perfection of freedom from the bondage of material work. The material fruitive results offered in the revealed scriptures are not the actual goal of Vedic knowledge, but are meant for stimulating the interest of the performer.
Devi Bhagavata Purana, Ninth Book, Chapter XXIX talks about both, following Sva-Dharma and Nishkama Karma.
ये विप्रा अन्यदेवेज्याः स्वधर्मनिरताः सति । ते यांति सर्पलोकं च पुनरायांति भारते । 36 ॥
हरिभक्ताश्च निष्कामाः स्वधर्मनिरता द्विजाः । ते यांति च हरेलॉक क्रमाद्रतिबलादही । 37 ॥
स्वधर्मरहिता विप्रा देवान्यसेवनाः सदा । भ्रष्टाचाराश्व कामाश्च ते यांति नरकं ध्रुवम्। 38 ॥
स्वधर्मनिरता एव वर्णाश्चत्वार एव च । भवंत्येव शुभस्यैव कर्मणः फलभोगिनः ॥ 39 ॥
स्वकर्मरहिता ये च नरकं यांति ते ध्रुवम्। भारते न भवंत्येव कर्मणाः फलभोगिनः ॥ 4o ॥
Those Brâhmanas that worship the other Devas and attached to their own Dharmas go to those regions of theirs respectively and again come to Bhârata. Attached to their own Dharmas, the Niskâmî Bhaktas of Hari go by their Bhakti step by step to the region of S’rî Hari. Those that are not attached to their own Dharmas and do not worship the Devas and always bent on doing things as they like without any regard to their Âchâras go certainly to hells. No doubt in this. The Brâhmanas and the other three Varnas, attached to their own Dharmas all enjoy the fruits of their good works. But those who do not do their Svadharma, go verily down into hells. They do not came to Bhârata for their rebirth, they enjoy their fruits of Karmas in hells!
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