Musing On the Mercy Seat

My current readings find me in Exodus. 
More recently, I have been in Exodus 25, which discusses the items of the Tabernacle. 
And I am curious. Exodus 25 discusses the construction of the Mercy Seat that goes on top of the Ark of the Covenant. 
The Mercy Seat. 
What a curious name for something that pertains so readily to an object known as being the symbol of the Law of Moses, which,  in the minds of many, has nothing to do with mercy. 
I wonder if it is so-called because the L-rd really wanted us to grasp that the concept of mercy really was a critical part of the dispensation of His law to Israel. 
Put another way, just as the exposition of the Beatitudes could be summed up in the Tenth Commandment, to beware of and keep far from even those thoughts that lead to unrighteous desire; so also the Law was really meant to convey a Mercy that the Pharisees and Saducees neglected to also skillfully exposit.