Abu Musa Al-Ash'ari (May Allah be pleased with him) reported:
Whenever a needy person would come to the Prophet (ﷺ), he would turn to those who were present and say, "If you make intercession for him, you will be rewarded, because Allah decreed what He likes by the tongue of His Messenger".[Al-Bukhari and Muslim].
Arabic/English book reference: Book 1, Hadith 246