This week's Torah portion begins with the story of the spies Moses sent to the Land of Israel. Twelve spies, one from each tribe, traveled throughout the Land to survey it and bring back their report to the people of Israel, who were waiting in the desert to enter.
The report they brought (ten of the twelve) was negative, to the point that the people did not want to enter the Land and, moreover, the Torah considers the report as sinful and is the root of the 38 years of wandering in the desert that the Jewish people spent before entering the Land of Israel.
However, when one analyzes Moshe's request and the spies' response in more detail, there is apparently no reason to think that they did anything different from what they were asked to do.
Moses told them to analyze the people who lived in the land, and they replied that they were strong. Moses asked them to see if they settled in open or walled cities, and they replied that they lived in walled cities. Moses asked about the produce of the land, and they brought samples of the fruits. So, what was the sin?
To understand this, we must analyze another issue. People often claim that observing the Torah and mitzvot is difficult. "I wasn't raised this way," "I'm not used to it," "I'm embarrassed," "What will my neighbor say?" etc., are some of the excuses commonly heard when discussing the topic.
However, there's a very basic point they're forgetting (or never even considered): a rational person won't demand something from another that the other person can't accomplish. This is especially true when the command comes from the one who made the command; for example, a potter who makes a clay vessel makes it in such a way that it can fulfill its purpose (holding water, for instance). It's just that humans can make mistakes, or simply not be skilled enough to achieve their goal.
How much more so God, the King of all kings, the Holy One, blessed be He, who is the essence of good and justice, who will not demand from the one He commanded, that is, the man to whom He commanded to do a Mitzvah (whom He Himself made) something that is not within his capacity or potential (which He Himself gave him) to fulfill (and regarding God it makes no sense to say that He makes a mistake or is not skillful...).
One must find the way and the path to be able to fulfill what God wants from us, but that it is possible, logically and rationally speaking, there is no doubt.
This was the sin of the spies sent by Moses. Although they answered each of Moses' questions satisfactorily and with reliable information, they added (of their own volition) a conclusion: One cannot enter the Land.
Moses never doubted the "what," that is, he never doubted that it was possible to enter the Earth, because God had commanded it. Moses sent spies to determine the "how," what strategy to follow to conquer the Earth within the limitations of nature. The spies reasoned that the "how" was complicated, the "what" was impossible...
The same applies to us, in all times and places. There is no doubt about the "what"—that is, that observing the 613 commandments of the Torah is possible (and obligatory). The question is how; we must seek the most appropriate path, each according to our situation and circumstances, in order to fulfill God's commandments in practice.