This week's parsha recounts the birth of theshevatim. When Leah gave birth to her fourth child, she exclaimed, "This time I will give thanks to Hashem; and she called him Yehuda" (Bereishis 29:35). Chazal tell us (Brachos 7b) that from the time the world was created, no one gave thanks to Hashem until Leah came along and gave thanks to Hashem. What prompted Leah to do what no one preceding her had ever done, and why did she wait until her fourth child to offer her thanks?
Rashi explains that our Matriarchs were prophetesses and they knew that Yaakov would beget twelve children. If they were divided equally, each of Yaakov's four wives would bear three children. Thus, when Leah gave birth to her fourth child, she realized that she had received more than her fair share, which inspired her to give thanks to Hashem.
Rav Wolbe (Alei Shur vol. II p. 282) elaborates on this idea. Regarding the mitzvah of bikkurim the Torah commands us to bring the first fruit to the Bais Hamikdosh and declare that the fruits are the produce of the land that Hashem promised our forefathers. Rashi (Devarim 26:3) explains that this declaration is necessary so that the farmer should not fall into the category of those who deny Hashem's kindness. Accordingly, we are obligated toacknowledge every kindness that Hashem bestows upon us. Yet, when He blesses a person with more than he deserves, he has an added obligation. He must now thankHashem for His great kindness.
Consequently, Chazal tell us there are four people that are obligated to give thanks to Hashem by offering akorban todah when the Beis Hamikdosh stands: one who survived a journey at sea, one who safely traversed a desert, a sick person who was healed and one who was freed from jail. These four people have received an added portion of Hashem's beneficence and therefore they must thank Hashem with a korban.
However, interestingly enough, we are witness to the fact that there are some sick people who, after being healed of their ailments, become weaker in theirruchniyos. Rav Simcha Zissel Ziv (The Alter of Kelm) writes that since the obligation to thank Hashem is so great at the time a person is healed, the yetzer hara does everything in his power to prevent the person from fulfilling this obligation. The yetzer hara contaminates this man's heart to prevent him from offering his thanks; thereby precluding any possibility for spiritual growth.
How many times a day are we the recipients of Hashem's kindness? The very least that we must do is to acknowledge these blessings. Truth be told, most of this kindness is more than we deserve. Thus, it is incumbent upon us to not only acknowledge His kindness but to thank Him for granting us more than is warranted by our merits. Indeed, every blessing is not only a kiss from Hashem, it is a test to see if we will ignore His benevolence, or fulfill our obligation and reciprocate by thanking Him for His lovingkindness!