Valmiki Ramayana Yuddha Kanda Sarga 6 Shloka 10

यः he who, गुणदोषौ: merits and de merits, न: not, निश्चित्य: deciding, व्यक्तम् failing to consider, दैवव्यपाश्रयः giving up faith in God, करिष्यामिइति: I will do it, कार्यम् task, उपेक्षेत् begins to do, सः he, नराधमः lowly one among men.

"He who fails to consider the merits and de merits, decides to do on his own and begins without faith in god saying, 'I' will do it, is a lowly one among men."