What instructions does the Quran provide about intercession, specifically regarding those who have the authority to intercede with Allah?
Intercession is by the most humble servants of Allah like the prophets and their deputies and very pious believers. They can intercede to help believers who need intercession after permission from Allah (SWT).
Allah Says in Sura Al-Anbiyaa', verse 30: They can not intercede except for whom Allah accepts ( to be granted intercession).
Wassalam.