Shiva Purana
एवं संपूज्य विधिवद्यथाशक्तित्ववंचयन् ॥ आददीत गुरोर्मंत्रं ज्ञानं चैव क्रमेण तु ॥ ८ ॥
Thus worshiping the Lord according to the prescribed rituals, he cheated Him according to his ability. Gradually one should chant the mantras and knowledge of the spiritual master.
english translation
evaM saMpUjya vidhivadyathAzaktitvavaMcayan ॥ AdadIta gurormaMtraM jJAnaM caiva krameNa tu ॥ 8 ॥
hk transliteration by Sanscript