The 6 branches of the Menora symbolize the 6 days of the week, and the center stem represents Shabbat. Just as the 6 lights of the Menora were all inclined toward the center light, so too all week we should remain mindful of Shabbat, which is the central focus of the weekdays. When I was growing up in Brooklyn, there was a bumper sticker on many cars which read, "Hang in there, Shabbat is coming!"

The Menora reminds us to utilize the years of our lives in this world to prepare for the ultimate goal – the World of Eternal Shabbat (YOM SHEKULO SHABBAT), the Afterlife.

The light from the Menora is symbolic of the fire of Torah (AISH DAT – Devarim 33). THE NUMERICAL VALUE, THE GEMATIRA of the word, Aish (ALEF SHIN) and of the word, Menorah, (MEM NUN VAV REISH HEH) are both equal to  301.

My Rebbe, Rav Pam Ztz"l, taught that the physical structure of the Menora is alluded to at the beginning of each of the 5 Books of the Torah. The first verse of Sefer Bereshit,  BERESHIT BARA ELOKIM ET HASHAMAYIM V'ET HAARETZ,    contains 7 words, corresponding to the 7 branches of the Menorah. 

The first verse of Sefer Shemot contains 11 words, V'EILEH SHMOT BNEI YISRAEL HABAIM MITZRAIMA ET YAAKOV ISH UBEITO BAU, corresponding to the 11 round knob shaped balls, decorating the 7 branches of the Menorah.

The first verse of Sefer Vayikra contains 9 words, VAYIKRA EL MOSHE VAYEDABEIR HASHEM EILAV MAYOHEL MOED LAYMOR, corresponding to the 9 flowers decorating the Menora's branches.

The first verse of Sefer Bamidbar contains 17 words, VAYEDABEIR HASHEM EL MOSHE BAMIDBAR SINAI B'OHEL MOED B'ECHAD LACHODESH HASHEINI B'SHANA HASHEINIT L'TZEITAM MEERETZ MITZRAIM LAYMOR , corresponding to the Menora's height.

Although the Talmud in Menachot states that the Menorah was 18 tefachim high, the Talmud explains that this measurement includes the removable bowl-like receptacles which sat atop the branches of the Menora and into which the oil and wicks were placed. These lamps were also made of pure gold but were separate from the Menora and were removed for cleaning out the lamps of the burnt out wicks and oil. Thus the Menorah itself without the removable lamps was 17 tefachim high, corresponding exactly to the first verse of Sefer Bamidbar.

The first verse of Sefer Devarim contains 22 words, AYLEH HADEVARIM ASHER DIBEIR MOSHE EL KOL YISRAEL B'AYVER HAYARDEN B'MIDBAR BAARAVA MUL SUF BEIN PARAN UBEIN TOFEL V'LAVAN V'CHATZEIROT V'DEE ZAHAV, corresponding to the 22 ornamental cups, decorating the 7 branches of the Menora.

Why was the Menora chosen to be the symbol of the Jewish State?  This is because the Menora teaches us the fundamental lesson that TORAT YISRAEL is bound up forever with  ERETZ YISRAEL AND AM YISRAEL.