Brihat Parashara Hora Shastra
गृहविंशोपकं वीक्ष्यं सूर्यादीनां खचारिणाम्। स्वगृहोच्चे बलं पूर्णं शून्यं तत्सप्तमस्थिते॥ ११॥
The Grahas from Sūrya on get full strength, when in exaltation, or in own Rāśi and are bereft of strength, when in the 7th (from exaltation).
english translation
gRhaviMzopakaM vIkSyaM sUryAdInAM khacAriNAm। svagRhocce balaM pUrNaM zUnyaM tatsaptamasthite॥ 11॥
hk transliteration by Sanscript