An Interesting Shloka from the "Vairagya Shatakam (A hundred verses on Renunciation)" written by the great poet Bhartruhari.

महेश्वरे वा जगतामधीश्वरे
जनार्दने वा जगदन्तरात्मनि ।
न वस्तुभेदप्रतिपत्तिरस्ति मे
तथापि भक्तिस्तरुणेन्दुशेखरे ॥

--> I see no difference between the Supreme Lord of this Universe, Maheshvara (Lord Shiva), and the Innermost Self (Soul) of this Universe, Janardhana (Lord Vishnu). However, my devotion is to Lord Indushekhara (Lord Shiva), the one holding the crescent moon on his head.