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तत्रैकाग्रं मनः कृत्वा यतचित्तेन्द्रियक्रियः ।
उपविश्यासने युञ्ज्याद्योगमात्मविशुद्धये ॥६- १२॥

tatraikaagraM manaH kRRitwaa yatachittendriyakriyaH ।

upawishyaasane yuJNjyaadyogamaatmawishuddhaye ॥६- १२॥

Source: Automatic ITRANS Transliteration

तत्रैकाग्रं मनः कृत्वा यतचित्तेन्द्रियक्रियः । उपविश्यासने युञ्ज्याद्योगमात्मविशुद्धये

There making the mind concentrated on a single object, controlling the consciousness, senses

in a ... posture by yoga self completely purify.

Source: Milind S. Pandit

Sitting (in a comfortable position) and concentrating the mind on a single object, controlling the thoughts and the activities of the senses, let the yogi practice meditation for self-purification.

Source: The Bhagavad-Gita: The Sacred Song