The “voice in the head” may or may not be the Holy Spirit. If that voices gives ten people ten different interpretations of the same passage, it’s most probably not.
All the more reason to test the spirits by the Word of God, instead of discounting His Word. The Holy Spirit glorifies the Son.
In my experience and the experience of those I know and those I read and hear about, the Holy Spirit doesn't works that way...
First thing is, you don't interpret the scripture...God does the interpreting...
What the Holy Spirit does is lead you to more scripture that will confirm or deny what you are researching...And more likely than not, he will do it with far more than just a couple of verses to get you good ground to stand on...
The key is not understanding what you are reading...The key is believing what your are reading...God will provide the understanding with the scripture to back it up...