Theory:

     One day the dog came running to him, putting his paws against his legs and motioning with his head to some spot behind. The old man at first thought his pet was only playing and did not mind it. But the dog kept on whining and running to and fro for some minutes. Then the old man followed the dog a few yards to a place where the animal began a lively scratching. Thinking it was possibly a buried bone or bit of fish, the old man struck his hoe in the earth, when, lo! a pile of gold gleamed before him.
 
     Thus in an hour the old couple were made rich. The good souls bought a piece of land, made a feast for their friends, and gave plentifully to their poor neighbours. As for the dog, they petted him till they nearly smothered him with kindness.
Explanation:
 
One day, Muko went running to its master, motioning to some spot on the ground. Initially, the farmer thought the dog was playing and so did not pay attention to Muko seriously. Finally, however, Muko did not leave him or withdrew its effort; it made crying sounds, and ran to and fro for some minutes, signalling him something.

The old man then understood that Muko was trying to convey some message to him. Then the old man followed the dog and reached a place where it began to scratch. The old man thought that the dog was scratching there, possibly because of a buried bone or bit of fish. So, he started to dig the place the dog showed him, expecting to find a buried bone or a bit of fish. But, instead, to his surprise, he found a pile of gold buried inside the earth, which shone before him brightly.
 
The old couple became rich suddenly in an hour. God blessed them with treasure as a gift for their kindness, hard work and love for other living beings. Their beloved dog made them rich. After then, the old couple bought a piece of land for themselves. They shared their wealth with their poor neighbours, which shows their generous nature, and arranged for a big feast for their friends.
 
The good old couple's feast for friends.jpg
Feast for friends
 
Also, after this incident, the love of the old couple towards their dog was increased. They showered more care and concern for it than before. They felt grateful for their pet dog and showed more love towards it. The good old couple were kind and merciful toward the animals, and they reaped the fruits of their kind nature.
 
Meaning of difficult words:
 
S.No
Words
Meaning
1.
Whining To make a loud, unhappy, crying voice
2.
YardA piece of land next to or around a house
3.
Feast A large or special meal
4.
SmotherTo cover something with too much of something
5.
MotionTo make action with your body parts to tell somebody about something
6.
ScratchTo rub or damage the surface with your nails
7.
Lo!An old word used for telling someone to look at something
Reference:
National Council of Educational Research and Training (2007). Honeycomb. The Ashes That Made Trees Bloom (pp. 55-63). Published at the Publication Division by the Secretary, National Council of Educational Research and Training, Sri Aurobindo Marg, New Delhi.