Yadupati
Death of Balarama - wood engraving from the 1860s Barddhaman edition of the Mahabharata in Bengali
Mahabharata 16.4: Proceeding to the forest , Krishna beheld Balarama sitting in a solitary spot. He also saw that Balarama had set himself to Yoga and that from out of his mouth was issuing a mighty snake. The colour of that snake was white. Leaving the human body that high-souled Nâga [Shesha Naga] of a thousand heads and having a form as large as that of a mountain, endued besides with red eyes, proceeded along that way which led to the ocean. Ocean himself [Varuna], and many celestial snakes and many sacred Rivers were there, for receiving him with honour.
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Commentary
So Balarama is seen as the avatara of Shesha Nag, the primordial unmanifest Matter or pradhana. When the pradhana becomes manifest we call that prakriti. In Hinduism it is common to see the energy (Shakti) of God as His spouse and as the Prakriti (Mother Nature) , but as gods are mostly androgynous it is also possible for the Shakti of a 'male' God to be represented by an another androgynous 'male'. Hence, in my opinion, this picture depicts Balarama as the Shakti of Sri Krishna.
Death of Balarama - wood engraving from the 1860s Barddhaman edition of the Mahabharata in Bengali
Mahabharata 16.4: Proceeding to the forest , Krishna beheld Balarama sitting in a solitary spot. He also saw that Balarama had set himself to Yoga and that from out of his mouth was issuing a mighty snake. The colour of that snake was white. Leaving the human body that high-souled Nâga [Shesha Naga] of a thousand heads and having a form as large as that of a mountain, endued besides with red eyes, proceeded along that way which led to the ocean. Ocean himself [Varuna], and many celestial snakes and many sacred Rivers were there, for receiving him with honour.
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Commentary
So Balarama is seen as the avatara of Shesha Nag, the primordial unmanifest Matter or pradhana. When the pradhana becomes manifest we call that prakriti. In Hinduism it is common to see the energy (Shakti) of God as His spouse and as the Prakriti (Mother Nature) , but as gods are mostly androgynous it is also possible for the Shakti of a 'male' God to be represented by an another androgynous 'male'. Hence, in my opinion, this picture depicts Balarama as the Shakti of Sri Krishna.