Mananeeya Eknathji gives here the definition of SERVICE from the doer's point of view: Working as instrument in total surrender to God's plan
That service is the best and the noblest, which is performed with the attitude of total surrender to God. "He has endowed me with all the possible capacities and I must utilize every mite of the energy, power, intellect, strength, and all other possessions to the best of my ability for the glory of my SELF. It is the divine design that I should render service on His behalf. Madarthamapi karmani kurvan siddhimavapsyasi B.G.12.10. He desires the betterment of the world and I am being used just as a tool or a means to carry out His design. I am just an instrument in His hands. Nimittamatram Bhava sayaachin B.G.11.33
We have to play our role in this world gymnasium with all vigour and enthusiasm. The best illustration of this type of service we find in the duties of a nurse. She treats the patient very kindly and sincerely. As soon as her duty is over, she hands over the charge to the next nurse and gets herself freed without any feeling of attachment. If the patient is cured and goes home she does not miss his absence, but serves the next patient with the same sense of duty. If the patient is serious, she does not feel anxious or if he dies she is not grieved. She has no attachment whatsoever nor obsession. But that does not mean that she does the duty indifferently or heartlessly. No, she puts her heart and soul into the care of the patient. But she looks at the things objectively. When we nurse a patient who is our relative, we have attachment and are visibly moved by any serious turn in his physical condition. It is because of the strong tie of relationship that binds us to the patient. It is thus clear that the action must be performed without any attachment but sincerely and honestly to the best of our ability with an attitude of being a tool only.
We have been called upon to execute whatever is essential and possible as willed by God. This is SERVICE. We are doing His work. Matkarma paramo bhava B.G. XII.10. Such work elevates us and leads to Self-realization, which is the supreme goal of human life. This work is done in freedom and not in slavery; for it liberates us from the cycle of births and deaths. Even the most trifling desires make us slaves and degenerate us. Here there is no slavery. In doing His work there is no slavery and there is no thought of success or failure. Sukhadukhe same kritva labhalabho jayajayau B.G.II.36.