http://revach.net/article.php?id=3468

Section:  Avodah   Category: Bnei Bayscha
Rav Shimon Schwab - The Ring That Binds Us
The outer walls of the Mishkan, the Kerashim, were made of gold covered wood.  "Viyihiyu So'amin Milmata, Viyachdav Yihiyu Samim Al Rosho, El Hataba'as",  (Truma 26:24).  The Kerashim had two hands protruding from the bottom but on top they were one and connected with a ring.

Rav Shimon Schwab says that the Torah is teaching us what a married couple looks like.  On the bottom they are matching like twins "Toamim".  The bottom represents gashmiyus, the physical realm.  Although every couple comes together as one, in fact they are two separate individuals.  However "Al Rosho" on top, which represents ruchniyus, "Yachdav Yihiyu Samim", they are indeed one.  Their thoughts, goals, and ambitions must be the same striving to build a home that will be Mikadesh Shem Shamayim.

"El HaTaba'as", this spiritual union is made through the ring.  While we can effect a marriage by any article worth a prutah, nevertheless we get married with a ring.  This is the ring that will make this couple into a Mishkan Hashem and create a home that is heaven on earth, just like the Mishkan of old.