Sforno on Exodus 18:1/ספורנו על שמות י״ח:א׳

1וישמע יתרו, the word שמיעה for hearing is used when recording or referring to something which did not occur at the time it is being reported. When one hears of something which is just happening, the Torah uses the term ראיה, “seeing,” i.e. first hand knowledge of something. It does not matter whether the sound of the happening comes from a distant location or is nearby within one’s eyesight. Examples of the use of the word ראיה “seeing” being used for matters which were heard second hand, not seen, are found in Genesis 42,1 where Yaakov, resident in the land of Canaan, is reported as “seeing” that there was grain for sale in Egypt. Clearly, the Torah refers to Yaakov having heard about it. Seeing the matter was not near at hand nor had occurred just then, the Torah used the words וירא יעקב, “Jacob saw.” A similar use of the word “seeing,” וירא for something not actually seen is Numbers 22,2 where Bileam is reported as “seeing” all that Israel had done to the Emorite kings. Bileam had not seen any of it, but had heard that the Israelites had defeated the two most powerful Emorite kings Sichon and Og. A third example confirming our theory would be Deuteronomy 28,10 where the people of the globe are reported as expressing their conviction that the Jewish people are G’d’s darlings and that they would therefore be in awe of them. Clearly, the people of the globe could not have “seen” this, but they had heard about the success of the Jewish nation. The events inspiring such feelings among the nations of the globe had occurred over a period of time, not all at once. However, if we understand the words כי הוציא as meaning כאשר הוציא, “when He took out,” we must understand Yitro as saying that he had heard all that G’d had done for Israel at the time when He took them out of Egypt. This would include a reference to all the plagues, the drowning of the Egyptians army, etc. It was this information which had prompted him to journey into the desert himself instead of sending a messenger who would accompany Tzipporah and her children so that they would be reunited with their husband/father. He was primarily motivated by his quest for G’d. This is similar to Chronicles II 32,31 where the king of Babylon wanted to have evidence of the reports he had received about the miraculous recovery from his illness which King Chizkiyah had experienced.