Below is my very humble ancient coin collection. 
This collection is in its beginning and is a new work very much under construction. 
As a professing AND practicing Christian I look at this hobby with some degree of apprehension. 
 
Many of these ancient societies in which these coins are from committed the sin of worshiping their emperors as gods. 
This is a very blasphemous sin from a true theological Christian point of view. 
 
In fact to worship even a dead emperor on a coin could be thought of by many Christian scholars as a for runner or even the actual sin of worshiping the beast as spoken of in the book of Revelations in the Bible. So my point is enjoy the history and novelty of the coins here but please by all means do not stand of awe of there images of the emperors. End of disclaimer.
 
I have a difficult time putting names, places and events of ancient history into long term memory. I believe by collection and study of coins helps me focus and visualize these past civilizations. Holding an ancient coin is sort of like holding a seashell in your hand and being able better visualize and have a feel for the oceans. 
 
I suppose collecting ancient artifacts such as pottery would have a similar effect as a memory aid. But such an artifact collection would cost much more and take up much more space.