Shiva Purana
शिवस्य वाचको मन्त्रश्शिवमूर्त्तेश्च वाचकः ॥ मूर्त्तिमूर्तिमतोर्भेदो नात्यन्तं विद्यते यतः ॥ २२ ॥
The Mantra that expresses Śiva expresses his idol too, since there is not much of difference between the idol and the original.
english translation
zivasya vAcako mantrazzivamUrttezca vAcakaH ॥ mUrttimUrtimatorbhedo nAtyantaM vidyate yataH ॥ 22 ॥
hk transliteration by Sanscript