Lentils are legumes that grow like peas and beans in a pod, with two lentil seeds inside.  They are fairly small and flat and when split into halves look like split peas. They never arrive fresh at the dinner table, but are cooked or boiled from dry and have an infinite shelf-life, one of the reason’s they were so popular with our ancestors. 

They are very rich in protein (about 26%) and thus provide a great dietary source to vegetarians.  Lentils are also very high in Vitamin C and the B vitamins, and contain eight of the essential amino acids.

There are hundreds of varieties of lentils, which range in color from yellow, orange, red, green, and brown to black and can be bought either with or without their skins. 
Their use dates back to approximately 6000 BC, when the Egyptians used them not just as a food source, but also as protection for valuable cargo.  Well over 100 tons of lentils were found cushioning the famous obelisk as it was transported to Saint Peter's Basilica in Vatican City.  They also put them into tombs to feed their kings and queens as they journeyed to their next life.  According to Christian belief, lentils were associated with mourning – Genesis 25:29 states, "The day Abraham died, Jacob boiled dishes of lentils and went to comfort his father."  Catholics ate lentils instead of meat during lent and in ancient Greece, lentils were used to make bread.

Today, lentils are used throughout the world, particularly Eastern Europe and India.  The famous Indian dish dhal utilizes the pulse with eight of the essential amino acids – with recipe variations the length and breadth of the country.

References:
1. The Encyclopedia of Healing Foods by Michael Murray, Joseph Pizzorno, and Lara Pizzorno.
2. Benders' Dictionary of Nutrition and Food Technology.
3. USDA National Nutrient Database for Standard Reference.
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