וירא פרעה כי היתה הרוחה. כמו ורוח לשאול: BUT WHEN PHARAOH SAW THAT THERE WAS RESPITE. The word harevachah (respite) is similar in meaning to ve-ravach (relief) in so Saul found relief (Jud. 16:23).
והכבד את לבו. שם הפועל. תחת פועל עבר: HE HARDENED HIS HEART. Scripture employs an infinitive (hakhbed) in place of a perfect.14In view of the fact that our verse deals with the past, Scripture should read hikhbid (he hardened) rather than hakhbed (to harden), as the former is a perfect and the latter an infinitive. I.E. points out that Scripture occasionally uses an infinitive with the meaning of a perfect. As to the question of free will, see I.E. on Ex. 7:3.