Theory:

     Meanwhile the envious neighbour peeped in at the window when the boiled beans were being ground.
 
     “Goody me!” cried the old hag, as she saw each dripping of sauce turning into yellow gold, until in a few minutes the tub under the mill was full of a shining mass of gold.
 
     So the old couple were rich again. The next day the stingy and wicked neighbour came and borrowed the mortar and magic mill. They filled one with boiled rice and the other with beans. Then the old man began to pound and the woman to grind. But at the first blow and turn, the pastry and sauce turned into a foul mass of worms. Still more angry at this, they chopped the mill into pieces, to use as firewood.
Explanation:
 
While the good old couple were working on their handmade mill and grinding their boiled beans, the wicked couple watched them secretly from the window. They were amazed to notice the magical mortar and mill. "Goody me!" exclaimed the bad old woman as she watched each drop of sauce turn to yellow gold. The tub under the mill was filled with a gleaming mass of gold in a matter of minutes.

Again, for the second time, the good old couple became rich. The wicked couple became very jealous, and so plotted a plan to be wealthy like their neighbours. They borrowed the mortar and magical mill from the good old couple, thinking to get gold out of those. They put boiled rice in the mortar and beans in the hand mill. The bad old man then began working on the mortar, and the woman started grinding on the mill.
 
However, the pastry and sauce turned into a foul mass of worms when the first blow and turn occurred. They were angry again.
 
For the first time, when the wicked wanted to be wealthy like the good old couple, Muko showed them the place of a dead kitten instead of treasure. For the second time, the mortar and hand mill gave out worms instead of gold. Still, they didn't realise their arrogance, stinginess and cruelty. They didn't understand the fact that being mean and wicked will only result in unhappiness. They were angry about being cheated again and smashed the mill into pieces to use as firewood. They did not even think about their goodhearted neighbours who lent their mortar and mill to them and destroyed the things they had lent.
 
Meaning of difficult words:
 
S.No
Words
Meaning
1.
PeepTo look at something secretly and quickly
2.
Envious Wanting something that someone does or have
3.
HagAn ugly, unpleasant old woman
4.
GleamingShining
5.
StingyNot generous or unwilling to spend money
6.
DripsSmall drops of liquid
7.
Foul Very bad or unpleasant taste
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.