Protection is extremely important in our opinion, just as there are good and bad in this life, it therefore follows that there will be good and bad in the next. Some people are fortunate enough to develop spiritually without ever experiencing any difficulties, they are the lucky ones, others may not be so lucky.
As with anything else, (you wouldn't try to construct something potentially dangerous without safeguarding yourself first,) it is common sense to put basic yet effective protection in place before you begin any kind of spiritual work.
One way to do this is to visualise a white bubble of light completely surrounding you, even if you can't visualise or see it, trust and know that it is there. When you have finished your spiritual work simply allow the bubble to disperse and visualise or send it out into the universe taking any negativity with it.
It seems very simple and will only take a few seconds but it's extremely effective and more than worth the effort.