“But Martha was cumbered about much serving, and came to him, and said, Lord, dost thou not care that my sister hath left me to serve alone? bid her therefore that she help me.” Luke 10:40
The problem with Martha may not be so much that she was serving, but that she was cumbered with it, meaning she was distracted by it. The true heart of a servant is they serve others as if they were serving Christ. Otherwise what happens, a person starts to complain, just like Martha did.