(one's) passport to (something) phrase
That which enables one to achieve, discover or get access to something good or worth having or doing.
This certificate is my passport to a decent job.
This phone is the police's passport to solving the crime.
A softly mellifluous voice is her passport to a professional singing career.
A resource that will allow the possessor to access to power, knowledge or understanding
The origin of this phrase is not clear.
If you have something on your person/body, it means that you are carrying it with you.
Customs officers found a gun concealed about your person.