"She sent her maidservant and she took it" [Shemot 2:5]
Chazal inform us that the basket carrying Moshe was too far for Pharoah's daughter to reach from where she was standing. Still, she stretched out her hand (amasah) in the direction of the basket and Hashem miraculously lengthened her arm for her.
R' Meir Shapiro, the rosh yeshivah of Yeshivas Chachmei Lublin, called for an emergency meeting of the leaders of Lublin to discuss a certain person whose life was in danger. R' Shapiro demanded of them to do something to save his life.
"This matter that you speak of" responded one of the leaders, "is beyond our capabilities. We regrettably do not believe that we can carry it out."
"In this week's parsha" replied R' Shapiro, "the Torah states: "And she sent her maidservant". Chazal teach us that the arm of Pharoah's daughter was miraculously lengthened in order for her to take hold of Moshe's basket.
"I wonder" continued R' Shapiro, "why did Pharoah's daughter even attempt to retrieve the basket in the first place? After all, if it is obvious to an individual that something is not within his reach, does he waste his energy trying to obtain it?"
"We see from here" concluded R' Shapiro, "that when a person is expected to accomplish something, he should not deliberate whether or not he is capable of succeeding - he must try! Let him first make an effort, and then Heaven will assist him."
Source: Rabbi Yisrael Bronstein