Vishnu holds in the four hands the Conch, the Discuss, the Mace and the Lotus. The Conch is the symbol of sound, the discus of time, the mace of power, and the lotus of the heart. He is the master of sound, time, power and the hearts of all beings. Similarly, Shiva holds in the hands Damaru (the drum), and Trishula (trident). Here Damaru stands for sound and Trishula for a three-pronged time. He is the master of time and sound. Thus, both are the same, only names and forms are different. Vishnu and Shiva are the same... Not to think so shows the narrow-mindedness of the devotee.

Here is an example in the context of Indian traditions. Both Vaishnavites and Shaivites visit Tirupati. There is only one God there. Shaivites call Him Venkateswara and Vaishnavites call Him Venkatraman. There may be difference in their feelings but God is one. They create differences in order to satisfy their petty minds. 

Another example. Shiva is called Pashupati, the Lord of pashu or beings. The individual with mind-principle are beings. Vishnu is called Gopala, the Lord of Cows or beings. Actually both mean the same. Only narrow minds create differences. Narrow minded people can never attain higher states whatever practices they undertake for any length of time. We should recognise the unity in diversity. This is true spirituality. You are yourself God. As long as you do not know this truth you are Jiva (individual); once you know, you are Deva (God). (SSS Vol.25)