By His Divine Grace A. C. Bhaktivedanta Swami Prabhupada
Shiva is dahi (yoghurt) and Krishna is milk. When you take pure milk and mix it with a little sour thing, it becomes dahi (yoghurt). Similarly, Krishna is pure spirit, and when this pure spirit is mixed up with maya, then that is Shiva. Lord Shiva is maya-adhipati. It was once inquired by Yudhisthira Maharaja that Lord Shiva, although he appears to be like a beggar, who does not possess even a house and lives underneath a tree, his (Shiva’s) devotees become very rich and opulent materially. Whereas although Lord Vishnu is lakṣmi-pati (husband of Lakṣmi, the goddesss of fortune) and vaikuntha-pati (master of the Spiritual World), the Vaisnavas (devotees of Vishnu) become beggars. Just opposite. By worshiping the beggar one becomes rich, and by worshiping the rich one becomes a beggar. Why is this contradiction?
So this is answered by Krishna, yasyāham anugrhnāmi harisye tad-dhanam sanaih [SB 10.88.8], “My first benediction to my devotee is that
I take away all his riches.” That’s all. Then when he becomes helpless, he becomes firmly convinced and when he has no other shelter, then automatically he takes shelter of Krishna. This is what Krishna demands, sarva-dharmān parityajya mām ekam [Bg. 18.66]. When he has no other help, he fully surrenders to Krishna. That is Krishna’s special mercy.
And so far Lord Shiva is concerned, he is the husband of mother Durgā, the supreme material power, srsti-sthiti-pralaya sādhana-saktir ekā chāyeva yasya bhuvanāni vibharti durgā [Bs. 5.44]. So the devotee of Shiva gets all material benediction, and Vaishnava, instead of material benediction, he gets all spiritual benediction. That is the difference.
[An excerpt from a lecture delivered on April 13, 1975 in Hyderabad, India]