Even if devotees excuse those who insult them, Krishna takes a diffrent position and he is strict on this matter. Krishna will not excuse or tolerate any insult of his devotees. If we want to please Krishna, we must never insult his devotees. — Lecture on Bhagavad Gita, 01.26-27, London, 1973.
Even a small service performed with love & devotion pleases Lord Krishna.
For the pleasure of the Lord, His devotees call Him by His Holy Name to render service unto Him, not to fulfill their own desires.
Simply we have to desire to please Him (Krishna) and not desire anything for ourselves. Then we become simply instrument for his will. This is the important essence of Krishna consciousness. — In his Letter to Atreya Rishi, 20th Oct, 1973.
One does not need great wealth, education or opulence to satisfy the Supreme Personality of Godhead. If one is fully absorbed in love and ecstasy, he needs to offer only a flower and a little water.
Srimad-Bhagavatam 5.3.6,
Srila Prabhupada
Total absorption in playing flute for pleasure of Lord Krishna.