For a recap on rapture and its benefits in meditation go to the questions and answers page. Now, let's take a close look at the potential dangers of rapture in meditation. Seasoned meditators know from their own experience that the pleasant sensations of rapture are most alluring. Rapture feels so good that many meditators get attached to it. So, what's the problem with that?
Meditation & Pleasure
For one, intermediate meditators that are just starting to experience rapture in meditation are generally so overwhelmed by its pleasant sensations that they completely forget about meditating and become totally blinded by these sense pleasures. With our inherent tendencies to grasp everything that is pleasurable, meditators tend to get stuck at this level.
By attaching to the pleasures of rapture, we cannot progress any further. So, every time rapture arises we stop meditating only to indulge in sense pleasures. Thus, becoming slaves to our own desires...
Meditation And Thinking
Another danger is that we may start congratulating ourselves for having achieved this level of proficiency. By doing so, we may get trapped in thinking when we're supposed to meditate. One thing has to be really clear, rapture boosts concentration and can support the meditation practice to a high degree. But in order to harvest these fruits, we must to let go of these pleasant sensations whenever they arise and continue with our meditation.
Spiritual Maturity
In the beginning, rapture is hard to resist. The energy is so refined compared to what we're used to and it's known to be addictive. However, with experience we grow used to these refined mind states which make it much easier to let go. This is referred to as spiritual maturity. So, by letting go of the pleasant sensations rapture works for us as opposed to against us.
I recommend that you acknowledge to yourself, "I feel rapture," every time it arises during meditation and immediately bring your attention back to the meditation object. Again, this is what's meant by spiritual maturity.
Remember, that even when you let go of these pleasant sensations, you'll still rest in a pleasant mind state but without attaching to it - so, you got everything to win by letting go...
Best of luck!