Sunan Abi Dawud Book 2, Hadith 65
The Messenger of Allah (ﷺ) commanded us to build mosques in different localities (i.e. in the locality of each tribe separately) and that they should be kept clean and be perfumed.
The Mosque (of the Prophet) was built in the land of Banu al-Najjar which contained crops, palm trees and graves of the disbelievers. The Messenger of Allah (ﷺ) said: Sell it to me for some price. They (Banu al-Najjar) replied: We do not want (any price). The palm-trees were cut off, and the crops removed and the graves of the disbelievers dug opened. He then narrated the rest of the tradition. But this version has the word "forgive" in the verse, instead of the word "help". Musa said: 'Abd al-Warith also narrated this tradition in a like manner. The version of 'Abd al-Warith has the word "dung-hill" (instead of crop), and he asserted that he narrated this tradition to Hammad.
After (praising Allah and blessing the Prophet) that: The Messenger of Allah (ﷺ) used to command us to build mosques in our localities and keep them well and clean.