Valmiki Ramayana Bala Kanda Sarga 29 Shloka 9
Original Shlokaस त्वं सुरहितार्थाय मायायोगमुपागत:। वामनत्वं गतो विष्णो कुरु कल्याणमुत्तमम्।।1.29.9।।
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विष्णो O Visnu, स: त्वम् such a god as you are, सुरहितार्थाय for the welfare of devatas, मायायोगम् by act of illusion, उपागत: have assumed, वामनत्वम् गत: assuming dwarfness, उत्तमम् supreme, कल्याणम् auspicious act, कुरु perform.
"O Visnu perform this supreme, auspicious act assuming the form of a dwarf through, the power of illusion for the welfare of the devatas'.