The Rebbe explains that the nature of the world is such that the more vital something is for our survival, the easier it is to obtain and the less expensive it is. For example, air. Air is unarguably the most vital thing for life. Now there is not a single country on earth that doesn't have air in abundance. And it is free of charge. It's not even taxed like water is. In all countries of the world air is free and abundantly available.
The next thing is water. Water is not equally available in every country of the world, but we find that most civilizations and most inhabited places are near water reserves. For the majority of the world's population we can say that water is fairly readily available and the price that one has to pay for water is not for the water itself, as much as for the service of having the water delivered. In other words, if somebody wants to go and draw the water from the well, or take it from a river, it's generally free of charge. If you want to buy bottles of spring water you have to pay for it, but if you want plain ordinary water it's free and abundant.
What's next on the level of necessity? Food. Now, even the least expensive and most basic foods, probably bread and grains, are probably the most plentiful and the most necessary. But you have to plant them, and producing crops requires effort. Even the simplest and cheapest food requires effort in its planning and its preparation. There is no food that doesn't require somebody to pick it. Rain can fall right into your backyard, but food doesn't come into your house; you have to go and get it. You have to plant it, you have to tend it, you have to reap it. And food costs money. It may not be that expensive, but it does cost some money. Of course, food that is more of a luxury, like smoked salmon, meat, chocolate and so on, is generally more expensive. The fact that something is more expensive generally proves that it is less vital for life. To survive you don't need chocolate. For life you need water and bread.
After food, the next most important need for humans is clothing. In order for a person to survive, you really don't need an all wool French two-piece suit. Putting aside for a minute the necessities of modesty and so on, if the weather is nice you can even survive without clothing. Clothing is not vital for life in the same way as food is. Clothing is only necessary to cover the body and protect it from the elements. Inexpensive clothing protects the body as well as expensive clothing. You don't need a leather coat or a fur coat to be warm. You can have a wool coat or an acrylic sweater and it'll do the same job.
Next in the hierarchy of human needs is shelter. In order to be protected from rain or the heat you don't really have to buy a house. You can live in a cave. There are tzaddikim who lived in caves for many years and they survived. A cave can shelter a person. A person can live with somebody else, or rent a room. It is not necessary to purchase your own house if we're talking about mere survival. If a person wants to own a beautiful villa that's fine, but you have to pay a lot of money for it. Which means that this is not vital for human survival or existence.
After these come the things that would not be classified as needs, but rather as desires. In this category are things like art, jewelry, beautiful things in a house, decorations. These things people like, they enjoy, but they're very expensive. And sometimes one piece of jewelry can cost more than a house. Now obviously an object that costs so much money is definitely not vital for survival, for health, or for peace of mind, and acquiring such things is very, very difficult. To make these expensive paintings or to go down to the mines to get these diamonds or to get the pearls from the bottom of the sea, requires tremendous skill and tremendous effort and risk, and that's why they cost so much money.
What is the Rebbe telling us? He's saying that just as in the material world there's a hierarchy, in which things that are more necessary are easier to get and are cheaper, whereas the things that are harder to get and more expensive are not as vital, so too in spiritual matters. In the spiritual world, there are certain mitzvos that are so vital for the survival of the soul that HaShem makes them easy. HaShem wants to make these mitzvos easy to do so that no Jew should have the problem of not being able to observe them.
As far as Purim is concerned -- there are seven mitzvos. Some of these mitzvos are more difficult to observe. For example, the mitzvah of hearing the Megillah. That one requires a lot of effort. First you have to have a scribe write a Megillah. He has to learn how to write it. He has to write it on parchment, which is expensive. The writing takes a long time. It has to be kosher, and so on. It is hard work to produce a kosher Megillah. Then you have to acquire the kosher Megillah. Then the one that reads it has to know how to read it with the right punctuation, the right tune, and so on. And then while you're listening, you have to concentrate. You're not supposed to miss even a word. That's hard. To concentrate for forty minutes or so and not miss a word requires much effort.
What is a simple easy mitzvah on Purim? The Rebbe says that among the mitzvos of Purim there are two that are very easy. The two that are easiest are matanos le'evyonim and mishloach manos. Matanos le'evyonim is observed by giving even a small amount of money to two people. If no poor person knocks on your door and you didn't happen to meet one in the street, don't worry. Take two coins, put them aside and say, "This is my matanos le'evyonim," and the first opportunity I have after Purim I'll give it.
The other mitzvah that's very easy is mishloach manos, because the halachah requires only that each person give two kinds of food to one person. Those fancy baskets that they sell that make a good profit for the ones that make them, are not required by Halachah. All you need is two ready-to-eat foods. You may not send raw fish or raw meat or unpopped popcorn. It has to be something that is edible as is. Everybody can find one person to whom to send two things. A couple of cookies and an apple is enough.
To make the seudah, however, is an awful lot of work for the balabusta. You can't just serve cookies and apples. You should have wine and meat. It's more expensive. You have to buy the meat, you have to cook it.
So we see that the two mitzvos which are easiest to observe are that way because they are the most important. Why are they the most important? Do you understand what I'm driving at? Why did HaShem make it that mishloach manos and matanos le'evyonim are the easiest of the mitzvos to do? You don't even have to have kavanah -- intention -- when you give shalach monos. You don't have to think about it, just do it. The reason is because they're the most important. Remember what we said about air being the cheapest because it's most vital. The most vital mitzvos are shalach manos and matanos le'evyonim. Why are these two mitzvos considered more vital than all the other mitzvos, even more important than hearing the Megillah?
Because all the other mitzvos the person does for himself. The seudah is for himself, hearing the Megillah is for himself, saying Al HaNissim is for himself, and so on. But matanos le'evyonim and mishloach manos are for the sake of somebody else. Helping another Jew, sharing with another Jew, reflect the caring and concern one Jew has for another. That is why they're the most important of all the mitzvos. And that is also why they're the easiest to observe.
The most important mitzvah of all is Ahavas Yisrael; as Hillel said, "The remainder of the Torah is simply commentary." Rabbi Akiva too, stated that this is the major principle of the Torah.
It is a basic teaching of Chassidus that without ahavas Yisrael there's no ahavas HaShem. A Jew cannot say, I love G-d but I don't love Jews. The best expression of ahavas HaShem is ahavas Yisrael.
If you don't love every Jew, then your love of HaShem is blemished. Because every Jew is part of HaShem. If you don't love every Jew it means you don't love every part of HaShem. There is a flaw in your love of HaShem. I'm not saying, look at me, you'll find in me the epitome of love of every Jew. I'm telling you this as an ideal. We are all striving together to fulfill it. Of course there are people who are easier to love, like family and friends, and there are other people whom it is more difficult to love. This is our challenge.