In Moshe’s final address to the people, he tells them how each of them must take care to observe and uphold the law to earn God’s blessing:

וְהָיָה עֵקֶב תִּשְׁמְעוּן אֵת הַמִּשְׁפָּטִים הָאֵלֶּה וּשְׁמַרְתֶּם וַעֲשִׂיתֶם אֹתָם וְשָׁמַר ה’ אֱלֹ-ךָ לְךָ אֶת הַבְּרִית וְאֶת הַחֶסֶד אֲשֶׁר נִשְׁבַּע לַאֲבֹתֶיךָ – It will be because you listen to these ordinances, keep and perform them, that the Lord your God will keep for you the covenant and the kindness that He swore to your forefathers. (7:12)

Why does Moshe alternate between the singular and plural תִּשְׁמְעוּן / לְךָ?

Perhaps it serves to teach us how as individuals, we fit into a broader community.

The Gemara in Shabbos tells a story of a non-Jew who proposed that if Shammai could teach him how to observe the entire Torah while he was standing on one leg, he would convert to Judaism. Interpreting this as mockery, Shammai chased him away with a piece of construction material. When he made the same proposal to Hillel and stood on one leg, Hillel simply said, “Love your neighbor as yourself. The rest is commentary, now go and study.”

Clearly, the notion of learning anything on one leg is absurd, let alone the subject matter, or the stature of his audience. But the most interesting part of the story is Hillel’s response.

How does loving your neighbor incorporate laws such as Shabbos, lulav, and every other mitzvah?

Perhaps Shamma turned him away because it is simply impossible for an individual to observe every law in the Torah; many are mutually exclusive. Only a man can only do some, and only by a woman can do others; some only by a Kohen, some only by a Levi, and some only by a king! How could anyone learn to observe the whole Torah?

Shammai chased him away with construction material – the imagery of which alludes to a building that has many component sections – rooms, ceilings, walls, and floors. Without its parts, there is no building.

In the same vein, a lone Jew is incomplete. Shamai’s response indicates that the Torah is not for individuals; it belongs to the Jewish People as a whole.

Hillel went one step further – he proposed how people can transcend their individuality and become part of something bigger.

The ultimate expression of וְאָהַבְתָּ לְרֵעֲךָ כָּמוֹךָ is כאיש אחד בלב אחד – one man with one heart – disparate parts forming one holistic unit.

We do not have separate identities for our hands or our feet. They all belong to one indivisible “me”.

We can not observe the entire Torah individually. But by forming a group, we can observe the whole Torah collectively. Arguably, shaping this cohesive identity is one of the Torah’s expressly stated goals.

R’ Yitzchak Lande notes that the Torah switches from plural to singular throughout because although there is a communal responsibility, we each have an individual’s duty to pitch in.

Moshe says וּשְׁמַרְתֶּם וַעֲשִׂיתֶם – we must collectively keep and perform the Torah, and then וְשָׁמַר ה’ אֱלֹ-ךָ, Hashem will protect you – the individual.

Because even the most observant person cannot keep the whole Torah – we can each only do the best we can.