Vaishnava Samhita: Vol. I, Book II , Chapter 4. Shloka 1
वत्सानां पोषणादेव यथा माता प्रहृष्यति ।
भक्तानां पूजनादेव तथा विष्णुः प्रसीदति ॥
As the mother derives pleasure in attending to her children, Bhagavan revels in taking care of and patronising His devotees.
Please check these: Excerpts from a discourse by our Sri Sri Muralidhara Swamiji
When Love towards Archavataram (God in form of deity in temple) becomes complete, Bhagavan also completely transcends the limitation of being a ‘stationary’ deity and starts playing with the devotees.