Adam Clarke on Ezekiel 16:21

To cause them to pass through the fire - Bp. Newcome quotes a very apposite passage from Dionysius Halicarnass. Ant. Romans lib. i., s. 88, p. 72, and marg. p. 75, Edit. Hudson: Μετα δε τουτο, πυρκαΐας προ των σκηνων γενεσθαι κελευσας, εξαγει τον λεων τας φλογας ὑπερθρωσκοντα,της ὁσιωσεως των μιασματων ἑνεκα. "And after this, having ordered that fires should be made before the tents, he brings out the people to leap over the flames, for the purifying of their pollutions." This example shows that we are not always to take passing through the fire for being entirely consumed by it. Among the Israelites this appears to have been used as a rite of consecration.