"And Yitro, the priest of Midian, the father-in-law of Moshe, heard all that G-d did for Moshe and to Israel his people, that G-d had taken the Israel out of Egypt" (Shemot 18:1). Of course, Yitro was not the only one who heard all that G-d had done. Yet he was the only one who was listening; the only one who cared enough and was moved enough to actually do something. While others likely were impressed to hear that a slave nation took on the worlds superpower, such lasted the 30 seconds or so they spoke about it. They then moved on with their daily activities. Yitro, on the other hand, saw this as a transformative moment and came to cast his lot with the Jewish people. What motivated him?
Yitro is described both as Moshe's father-in-law and as a priest of Midian. It is understandable that Yitro cared greatly and took much pride in the accomplishments of his son-in-law. And the feeling was mutual: "And Moshe went out to greet his father-in-law, and he bowed and kissed him". Even before we are instructed to honour our parents, the Torah portrays the great respect one must have for our in-laws. Yet family ties do not always bring such behavior. Sefer Breisheet is rife with bickering families, and jealousy of one's closest kin is the norm more than we would like to admit.
In addition to being Moshe's father-in-law, Yitro was also the priest of Midian. As a sincere man of religion--and Rashi notes that he was "conversant in all the idolatries in the world, for there was not a god he did not worship"--Yitro sought the truth and saw the hand of G-d around him. As Maimonides explains (Laws of Idolatry 1:1), idolatry was rooted in a mistaken search for G-d, and Yitro was great enough to be open to reevaluate his beliefs as he sought the best path to worship G-d.
Yet one cannot just erase one's past: "Vayichad Yitro, Yitro rejoiced at all the good that G-d did for Israel". Noting the unusual word for joy, vayichad, our rabbis comment that his body became "chidudim chidudim, prickly prickly; he was grieved over the destruction of Egypt, that is why people say of a proselyte, for ten generations do not belittle an Armenian in his presence". It is human nature to be connected to one's past--even if one has radically changed course. So while Yitro was happy, he had counter feelings of despair for those to whom he used to identify with--our Sages say Yitro was one of Pharaoh's advisors. Having such feelings is natural and even healthy. What matters is what one does in practice, and in the next verse we read, "Yitro said: blessed is the Lord who has delivered you from Egypt and from Pharaoh, who has rescued the people from the hand of the Egyptians". Sure, Yitro had mixed feelings--even we must pour out wine to express our sorrow at the suffering of the Egyptians--but he realized that such punishment of Egypt was necessary.
For all his joy and identification with the Jewish people, the Torah is vague on what became of him. Moshe clearly wanted him as an advisor and the Torah does not tell us whether he accepted Moshe's pleas to remain (Bamidbar 10:29-35). I find it fascinating that Moshewas pleased that "you shall be eyes for us".
May we be able to use our eyes and truly see what is around us, so that we may hear the sounds of G-d.