Sparring is an essential aspect of martial arts training. It is one thing to learn the technique, it is another to actually apply it. Whether it is bag work, partner drills, or a lesson with the instructor, anyone can do something in practice. But then when they put it into practice everything falls apart. This is where sparring starts to come into play.
Drills are not stressful. That is why it is so easy to do them well. Sparring however, adds a lot more stress to the training. Someone is actually trying to hit you with a limb or weapon, or actually trying to choke or joint lock you. Sparring replicates, as best as it is possible to, actual combat or competition.

Sparring is the best way to get good fast. It is also much more dangerous. You learn quickly because everything that is learned is immediately applied with the added incentive of imminent bodily harm. The bodily harm part is where the danger is. Because sparring involves live fighting, even if reserved in power, people can get hurt if mistakes are made. This is especially true for beginners as they have much less combative experience.
Aside from the risks and rewards that are associated with fighting and sparring, it’s just fun.
The first experience I had with sparring was through fencing. Practice had a mix of drills, live bout (fencing match is called a bout) scenarios, and just straight fencing. The fencing and scenarios helped me more than anything when I started. I would learn stuff and then practice using it so that it would work in competition.
The first day I walked into the dojo I was sparring (in jiu jitsu it’s called “rolling”). The class starts with rolls to warm up, goes into a class lesson, and ends with more rolls. The philosophy of my sensei and his teacher is that rolling and practicing live is necessary.
For fencing and jiu jitsu, it’s much easier to spar because it is safer than for something like muoi thai. Fencing is no longer fought to the death or first blood, and you wear a lot protective equipment. Jiu jitsu is a very controlled art. The pressure and power applied to chokes, locks, and positions is easily controlled. This makes the open rolls relatively safe compared to striking arts.
Striking martial arts are a lot harder to control. Even the most restrained fighters can still hurt each other by accident. A light strike at an opponent who is stepping forward can still knock that person down. When I started muoi thai I immediately started sparring. It is a lot of fun and helps me learn just like with fencing and jiu jitsu.
I strongly encourage anyone who wants to do any martial arts to start sparring as soon as possible. It may be intimidating at first, but is really fun. You will learn a lot about the fight, reacting and thinking under stress, and controlling your body’s responses of fear—thus placing the mind in more complete control of the body.