It is reported about Sayyiduna Bilal (may Allah be pleased with him) that he said: "O Messenger of Allah! People engage in trade and buy and sell, and we are not able to do that." The Prophet (peace and blessings be upon him) said: "Are you not pleased that on the Day of Resurrection the mu'adhdhins will be the people with the longest necks?"
Al-Tabarani recorded it in al-Kabir, and al-Bazzar recorded something similar; its narrators have been declared trustworthy.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الصلاة / 1832