The Lord can be served simply by adoring Him and accepting Him.
Srimad Bhagavatam 2.9.36,
The best use of power and opulence is to engage them in the service of the Lord.
Srimad Bhagavatam 1.15.5
A devotee should always aspire to live in the association of advanced devotees and engage in the service of the Lord through the parampara system.
As a kshatriya has no problems while taking the wounds on his chest. similarly a devotee has no problems taking wounds while serving Krishna.
Determination means to serve Krishna inspite of bodily inconveniences.