The first Pasuk in this week’s Parashah states, “VaYishma Yitro Chohein Midyan Chotein Moshe Eit Kol Asher Asah Elokim LeMoshe ULeYisrael Amo Ki Hotzi Hashem Et Yisrael MiMitzrayim,” “and Moshe’s father in-law, Yitro, the chieftain of Midian, heard all that God had done for Moses and for Israel, His people, that the Lord had taken Israel out of Egypt” (Shemot 18:1). Immediately after this Pasuk, the Torah states that Yitro took his daughter and Moshe’s two sons, and proceeded to travel to Moshe. Rashi comments on the first Pasuk and asks what exactly had impressed Yitro so much to generate the response of coming to Moshe. Rashi answers that the events of the splitting of the Red Sea and the war with Amalek had inspired Yitro to draw nearer to Moshe and Am Yisrael.
Many Acharonim question Rashi’s approach, and ask why Rashi did not include the miracles of the Esser Makot Mitzrayim, the Ten Plagues of Egypt, as a part of Yitro’s stimulus to travel to Moshe and Bnei Yisrael. Surely the Ten Plagues were a miraculous event, worthy of being an inspiration to Yitro!
The Noam Elimelech attempts to resolve this perplexing difficulty. Often, the Yeitzer HaRa will mislead a person into believing that certain miracles are just natural occurrences, and are not of divine origin at all. However, this concept does not apply when a Tzaddik initiates the miracle through the power of his Tefillah. The Noam Elimelech states that this is the most amazing type of miracle, and it has the power to convince man that Hashem and His people are true. The two miracles which Rashi lists both had this unique property of being initiated by a Tzaddik. By Keriat Yam Suf, Moshe Rabbeinu lifted his staff towards the Yam Suf, and Hashem made it split. It was Moshe who initiated the miracle through the lifting of his staff! The same applies to the miracle which occurred by the war with Amalek. It was Moshe who initiated the miracle of Bnei Yisrael’s victory through the lifting of his hands towards the heavens, a sign of Tefillah!
The following story about the Meshech Chochma, Reb Meir Simcha HaKohein, further illustrates this point:
In the city of Dvinsk, there were non-stop days of pouring, heavy rain. The Daugava River was steadily rising, and all of the citizens of Dvinsk, Jews and non-Jews alike, were getting worried that the river would flood the city badly. They erected barriers, tried digging trenches, reservoirs, levees and detention basins, but nothing worked against the ever-rising river. They brought priests and Rabbanim to try to stop the rising of the river, but nothing was working. Finally, one person suggested asking the Meshech Chochma for guidance. They found him in the Beit Midrash, learning as if nothing was happening outside. They begged him to beseech the Heavenly Court to stop the decree. The Meshech Chochma stopped his learning and said that he would try. When the messengers came back, the river was dangerously high. A couple of hours passed, and Reb Meir Simcha finally arrived on the scene. He entered the banks of the river and stood there quietly, in deep concentration. A couple of minutes passed, and the river was almost overflowing the barriers. Another couple of minutes passed, and the situation had become even more dangerous. The Gadol uttered some inaudible words, and all of a sudden, the rain immediately stopped! The town was saved, and all of the non-Jews were amazed at the miraculous Rabbi. Everyone, Jew and non-Jew, proceeded to thoroughly thank the Meshech Chochma. From then on, all the non-Jews of the town trembled at the name Reb Meir Simcha, remembering the event that had taken place at the river. 
This story perfectly illustrates the power of Tefillah that a Tzadik has. May the Tzaddikei HaOlam daven for us in our time of need, and may they show the world the trueness of Hashem and His people.