Matthew Poole and continuators on Exodus 12:9

9 Eat not of it raw, nor sodden at all with water, but rost with fire: his head, with his legs, and with the purtenance thereof.

(i. e.) Not throughly roasted, for such we also say is raw, and so the Hebrew word na is understood by the Iewish and other Doctours. It signified, that Christ should suffer, as well as save, to the uttermost, all that was due for our sins.

Heb. the inwards, which were to be taken and washed, and then to be rosted together with the rest. Some do here except the fat and caul and kidneys, which were reserved by God for himself, 2 Chron. 3[illegible: 1+ letters]. 12, 14. But that exception was not made till after this time, and it seems not certain that that exception extended to the Paschal lamb. These and the head and legs are here mentioned not to exclude other parts but because they are not commonly roasted, but God would have the whole lamb roasted and eaten, to signifie, that we must have either nothing of Christ or the whole Christ, and all his benefits, his spirit to sanctifie and rule us as well as his blood to save us.