Hadith: No one has ever eaten food better than that which his hands have earned. Indeed, Prophet Dawūd (peace be upon him) used to eat from the earnings of his own hands

عن أبي هريرة رضي الله عنه عن النبي صلى الله عليه وسلم قال: «كان داود -عليه السلام- لا يأكلُ إلا من عمل يده». وعن المقدام بن معد يكرب رضي الله عنه عن النبي صلى الله عليه وسلم قال: «ما أكل أحد طعاما قط خيرا من أن يأكل من عمل يده، وإن نبي الله داود صلى الله عليه وسلم كان يأكل من عمل يده».
[صحيحان] - [حديث أبي هريرة رضي الله عنه: رواه البخاري. حديث المقداد رضي الله عنه: رواه البخاري]

Abu Hurayrah (may Allah be pleased with him) reported that the Messenger of Allah (may Allah's peace and blessings be upon him) said: "Dawūd (peace be upon him) used to eat only from the earnings of his own hands." Al-Miqdām ibn Ma‘d Yakrab (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) said: "No one has ever eaten food better than that which his hands have earned. Indeed, Prophet Dawūd (peace be upon him) used to eat from the earnings of his own hands."
[Sahih/Authentic with its two versions] - [Narrated by Bukhari]

Explanation

The Prophet (may Allah's peace and blessings be upon him) informed us that Dawūd (peace be upon him) used to eat only from the earnings of his labor. He was a craftsman who was good at making shields and other fighting tools. Since the prophets (peace be upon them) used to work and eat from the earnings of their labor, whether that consisted of craftsmanship, agriculture, sheep herding, etc. This is altogether the reason why those who are of a lesser rank are more required to earn through their own labor and avoid the embarrassment of having to ask people for money.