"And they shall make a Temple for Me, and I will dwell among them..."
In the (Medrash) Pesikta, it says that when G-d said this, Moshe
trembled. "How is it possible to build a house for G-d, who encompasses
and transcends all the heavens?" And G-d replied, "not by my standards,
but in accordance with their abilities: twenty boards in the North..."
Then when G-d began to discuss the sacrifices, Moshe said, "would all the
animals in the world provide even a single fitting sacrifice?" And G-d
replied, "not like your thinking, but a single sheep in the morning..."
And when G-d began to discuss the annual gift to the Temple, "each person
in redemption for his soul," Moshe again said "how could a person ever
give enough to redeem himself?" And once again, G-d replied, "not like
your thinking, but one-half Shekel according to the sanctified Shekel
The Chofetz Chaim learns from this Medrash that G-d does not make
impossible demands upon us. Every person is obligated to do only that
which he or she can. As King Solomon said in Mishlei (Ecclesiastes) 9:10,
"All that you find within your ability to do, act upon it..." which is to
say, only that which is within your ability. We must do only that which
has been placed upon us.
Every person is obligated to study, but according to one's abilities --
be that Mishna, Talmud, or Codes of Law. Similarly, a person is obligated
to give charity according to his or her wealth. A wealthy person cannot
give only the amount expected of a poor person, and claim to have
fulfilled his or her obligation, but neither should a poor person give
away everything trying to meet the standards of the rich.
A person must not become discouraged, worrying that it is impossible to
do everything -- and then do nothing. On the contrary: we must do
everything that we can!