The Prophet (ﷺ) said, "When the people of Paradise will enter Paradise and
the people of Hell will go to Hell, Allah will order those who have
had faith equal to the weight of a grain of mustard seed to be taken
out from Hell. So they will be taken out but (by then) they will be
blackened (charred). Then they will be put in the river of Haya'
(rain) or Hayat (life) (the Narrator is in doubt as to which is the
right term), and they will revive like a grain that grows near the
bank of a flood channel. Don't you see that it comes out yellow and
twisted"
Sahih al-Bukhari Book 2, Hadith 15