Jethro Rejoices In Yahweh With The Leaders of Israel (Exodus 18:9-12).
a Jethro rejoiced for all the goodness which Yahweh had done to Israel in delivering them from the hands of the Egyptians (Exodus 18:9)
b Jethro says, ‘Blessed be Yahweh who has delivered you out of the hands of the Egyptians and out of the hand of Pharaoh, who has delivered the people from the hand of the Egyptians' (Exodus 18:10).
c He declares his new vision of Yahweh. ‘Now I know that Yahweh is greater than all gods, yes, in the things in which they dealt proudly against them' (Exodus 18:11).
b Jethro takes a whole burnt offering and sacrifices for God, thus offering blessing to God (Exodus 18:12 a).
a Aaron and all the elders of Israel come to eat food with Moses' father-in-law before God (Exodus 18:12 b).
Note in ‘a' how Jethro's acknowledgement of the goodness of Yahweh and of His doings results in the parallel in Aaron and the elders of Israel coming to eat with him. While in ‘b' He blesses Yahweh and His declaration of the supremacy of Yahweh results in his offering a whole burnt offering and sacrifices to God, and thus in his ‘blessing' Him. In ‘c' He has been caught up with Israel in Israel's God and acknowledges His overall superiority.
‘And Jethro rejoiced for all the goodness which Yahweh had done to Israel in that he had delivered them out of the hands of the Egyptians.'
Here it is the deliverance that Jethro concentrates on. He had not seen the wonders but he does understand fully the one outstanding fact of the wonderful deliverance out of Egyptian hands. What amazed him was that Yahweh had delivered Israel from the powerful Egyptians, and he could only rejoice in it.
‘And Jethro said, “Blessed be Yahweh who has delivered you out of the hands of the Egyptians and out of the hand of Pharaoh, who has delivered his people from under the hand of the Egyptians. Now I know that Yahweh is greater than all the gods, yes in the thing wherein they dealt proudly against them.”
Jethro praises Yahweh for what He has done in delivering Israel. The repetition of ‘who has delivered' emphasises his wonder at what has happened. With Exodus 18:9 the deliverance is emphasised three times. Egypt was notorious as the region's super-power, ruled by a god and with powerful gods. But this has not prevented Yahweh from setting them at nought. Note the contrast with Exodus 18:8. Here it is ‘delivered --- Egyptians --- Pharaoh.' There it is ‘Pharaoh --- Egyptians --- delivered.' The unity of these verses is clear.
“Now I know that Yahweh is greater than all the gods.” Here he means the gods of Egypt, not his own god whom he possibly equates with Moses' God, Yahweh (compare the situation with El Elyon - Genesis 14:18-22). We cannot, however, see him as directly a worshipper of Yahweh or Exodus 18:12 would say so. Here Jethro speaks of Yahweh and not Elohim (God) because he has been told what Yahweh had done.
“Yes in the thing wherein they dealt proudly against them.” Nehemiah 9:10 suggests that this means ‘in the things in which the Israelites, through their God Yahweh, dealt proudly (with superiority) against the Egyptians', but in context here it must include the Egyptians and their gods as having acted proudly against Israel.
‘And Jethro, Moses' father-in-law, took a burnt offering and sacrifices for God, and Aaron came, and all the elders of Israel, to eat food with Moses' father-in-law before God.'
This is in Jethro's territory and he is Moses' clan leader and priest of the area, ‘the priest of Midian' (Exodus 18:1). It was therefore natural that Jethro should offer the sacrifices, both of the whole burnt offering which was presumably (as later) wholly burnt up and of other sacrifices, thank offerings, of which the flesh was available to eat. Note that these are offered to ‘Elohim' not Yahweh. The Midianites may well have worshipped El under some title, whom they could all equate with Yahweh, as Abraham equated El Elyon with Yahweh (Genesis 14:22).
“To eat food with --- before God”. This was an act of worship and acknowledgement of submission to ‘Elohim' (God). There is no suggestion that Jethro taught them anything. When he did, as his clan leader, seek to guide Moses, we are specifically told so, but it had nothing to do with religion. It was the senior administrator passing on his advice to his son-in-law. Moses who had been with the tribe of Jethro for many years, and seemingly had worshipped with him, clearly saw the God whom Jethro worshipped as equatable with Yahweh.
We can compare how Melchizedek, who as king of Salem and its surrounding area would have rights over Abraham, who paid him tithes as a user of his lands, provided the food and wine for a feast on the return of Abraham, he did so as a priest of El Elyon, and Abraham received them in the name of ‘Yahweh, El Elyon'. (Genesis 14:18-24). The situation is somewhat similar.
Note how here the text has changed from using ‘Yahweh' to using ‘God'. A ‘stranger' is among them. To him Yahweh is not all. Thus while making quite clear to Jethro that it is Yahweh Who has delivered Israel, he condescends to his father-in-law by mainly speaking of ‘God' throughout the passage.