The lack is the most important, and it is called a Kli [vessel] to receive the filling. The amount of the filling is measured by the size of the lack.
It follows that if there is the exact same filling, not more and not less, yet one enjoys the filling and is delighted and happy and cannot find words to express his joy, while the other feels that he has no pleasure whatsoever with which to sustain his soul, and sometimes feels as though he is fed up with life itself because he does not feel any purpose in his life.
For example, a healthy man, whose body is well and all his organs are healthy and well, yearns to receive delight and pleasure so he will have something with which to sustain his soul with some pleasure, but he does not succeed.
At the same time, another person is suffering from some illness and the doctors decided that he needs an operation but they do not know if the operation will succeed and his very life is in danger. He has seen several experts but they did not make any promises that he will be able to go on living.
And then, a wise man came and gave him a cure that helped him. Later, when he came to the doctors to do tests for his illness, they determined that he was completely well and there was nothing wrong with him. Clearly, at that time he is delighted and cannot say that he has nothing from which to derive vitality. Instead, his joy is immense.
At the same time, the first one, although he is healthy, he cannot receive vitality from his health because he does not have a Kli of lack of health. Hence, this filling gives him no vitality.
The question is, Is the filling that delights him true or is it imaginary?