Sayyiduna Maysarah al-Fajr (may Allah be pleased with him) said: I said: O Messenger of Allah! Since when have you been a prophet? He (peace and blessings be upon him) said: "When Adam (peace be upon him) was between the soul and the body."
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17958