Narrated by Abdullah ibn Amr ibn al-‘As (Radhiallaho anho):
Allah’s Messenger (sallAllaahu ‘alaihi wasallam) said:

When you hear the Mu’adhdhin (who says Adhan), repeat what he says, then invoke a blessing on me, for everyone who invokes a blessing on me will receive ten blessings from Allah: then beg from Allah al-Wasilah for me, which is a rank in Paradise fitting for only one of Allah’s Servants, and I hope that I may be that one. If anyone who asks that I be given the Wasilah, he will be assured of my intercession.

Sahih Muslim Number 747