Shiva Purana
यथा काष्ठेष्वनारूढो न वह्निरुपलभ्यते ॥ एवं शिवो ऽपि मूर्त्यात्मन्यनारूढ इति स्थितिः ॥ १४ ॥
Just as fire cannot be obtained without its being, mounted in the twigs so also Śiva is not known or understood without its being superimposed in the idol.
english translation
yathA kASTheSvanArUDho na vahnirupalabhyate ॥ evaM zivo 'pi mUrtyAtmanyanArUDha iti sthitiH ॥ 14 ॥
hk transliteration by Sanscript