The Midrash (Rus Rabba 2:14) states, "Megillas Rus doesn't discuss the halachos of וטהרה טומאה or והיתר איסור. So why was it written? It was written to teach us the reward for those who do chesed.”
This can be one reason we read Rus on Shavuos; the message of the Torah is gemilus chasadim.
The first five of the Aseres HaDibros are mitzvos למקום אדם בין, our obligations to Hashem. The remaining five are לחבירו אדם בין, the mitzvos and obligations we have toward our fellow man.
There are far fewer words in the second luchos. To keep the two luchos symmetrical, points out the Mabit, the words on the second לוח were written in larger letters than the first. Now, both luchos were covered with the same amount of writing.
Large letters attract attention as if they are shouting. The mitzvos of bein adam lechaveiro draw more attention than the mitzvos bein adam lamakom, indicating that our obligations to our fellow man are even more critical than our obligations to Hashem.
The Rosh (Pei'ah 1:1) writes, יותר חפץ ה"הקב אדם שבין מבמצוות הבריות רצון גם בהם שיעשה במצוות לקונו , "Hakadosh Baruch Hu desires more the mitzvos of helping your fellow man than the mitzvos that are solely for Hashem."
One year, the Tiferes Shlomo of Radomsk zt'l traveled to Kozhmir to be with Rebbe Yechezkel of Kozhmir zt'l on Shavuos. Rebbe Yechezkel of Kozhmir asked him, "Why did you leave Radomsk? You have chasidim there, and they want to be with you.”
The Tiferes Shlomo explained that he also wanted to grow in avodas Hashem and must go to his Rebbe.
Rebbe Yechezkel of Kozhmir explained that his role as a leader is to help others, even at the expense of his spiritual growth. He proved it from the following source. It states (Shemos 19:14) העם על ההר מן משה וירד, "Moshe descended from the mountain to the people," and Rashi writes, לעסקיו פונה משה היה שלא מלמד העם אל ההר מן אלא , "This teaches us that Moshe didn't tend to his own business. He went straight from the mountain to the nation."
What business did Moshe have? He wasn't a businessman! The answer is that the pasuk refers to Moshe's quest for spiritual growth. Moshe wanted to prepare for matan Torah. He wanted time in solitude to sanctify himself and prepare for this holy moment. Nevertheless, Moshe disregarded his own needs and focused on helping Klal Yisrael. Every leader of Bnei Yisrael must do the same. They must be devoted to their community, even at the expense of their growth.
The Pele Yoetz (Yomim Tovim) writes, "On yom tov, we must bring joy to the poor. Therefore, before yom tov, give tzedakah to the poor – each person according to his abilities. The Zohar says: 'On yom tov, Hakadosh Baruch Hu visits the homes of the poor, and if they don't have enough food, Hashem cries for them.' The Zohar writes, 'If a person is happy himself, and doesn't give to the poor, he will be punished...' Therefore, don't forget to give tzedakah to the poor before each yom tov. Give tzedakah in accordance with the amount Hashem gave you. Don't be satisfied with giving a little because you should give in accordance with your wealth. And after you help the poor, you can be happy and rejoice, and nothing bad will befall you, and there will be peace in your home."
Regarding Shavuos, the Torah states (Devarim 16:10-11) ...ושמחת ...אלקיך 'לה שבועות חג ועשית בקרבך אשר והאלמנה והיתום והגר ...ובתך ובנך אתה , "Make the holiday Shavuos for Hashem your G-d... and be happy...you, your son, your daughter...the convert, the orphan, and the widow that is among you."
Rabbeinu b'Chaya writes, "The obligation [to help the poor for yom tov] applies for all holidays... [Nevertheless], the Torah writes the mitzvah about Shavuos because Shavuos is one day, while Pesach and Succos are seven and eight days. One might think giving tzedakah before Shavuos isn't as important as giving before the other yomim tovim. Therefore, the pasuk emphasizes that we shouldn't be lenient... We must give tzedakah for Shavuos, just as we must for all other holidays..."
One reason for this is that the message of the Torah is chesed, to help one's fellow man. So, when you accept the Torah on Shavuos, do so with a desire and plan to help your fellow man.
