Commentary Par IX 77-78

It is probably no accident that Dante speaks here of the Seraphim, the highest order of angels and associated with the highest form of affection, spiritual love.  Folco was, after all, a poet of carnal love, but one who transformed himself into a better kind of lover when he took orders and then when he became God's flail for heresy.  Starting with Jacopo della Lana (DDP Lana.Par.IX.73-79) and the Ottimo (DDP Ottimo.Par.IX.73-78), the early commentators found biblical sources of the six wings of the Seraphim either in the Apocalypse or in Ezechiel.  However, beginning with Lombardi (DDP Lombardi.Par.IX.77-78), the consensus had moved to Isaiah 6:2, the only passage specifically naming them in the Bible: 'And above [the Lord's throne] stood the seraphim; each one had six wings; with two he covered his face, and with two he covered his feet, and with two he did fly.'