The concept ‘doctor’ is a word of the same family (or root) as ‘doctrine’, ‘docile’, ‘doctus’, ‘document’, etc. ; and that refers to everything that touches teaching, education.

     In fact, while doctor (<Lat. doctor, “he who teaches, master”, from the latin verb docere, “to teach, to educate, to show, to get someone seen”) means “teacher”; the other ones mean respectively:  doctrine (<Lat. doctrina, “theory, theoretical training”), “teaching, science”;  docile (<Lat. docilis, “disposed to educate oneself, he who learns easily, [fig.] “that one handles easily”), “he who learns easily without resistance”;  doctus (<Lat. doctus “who learned, who knows”), “educated”;  document (<Lat. documentum, “lesson, model, demonstration”), “enquiry, teaching”.

In other words, to teach (doctor) and strengthen a disciple of Christ, we need a teaching (Divine Doctrine); and to have the Genuine Teaching of the Lord, we need to be disposed (docile) to learn patiently and at length (doctus) in order to amass more ‘solid foods’ (documents) than the ‘spiritual milks’.

Documentary research that makes a doctor [teacher] be a potential researcher is a scientific research lying in documents (books or proof-objects) that enquire or inform, that teach or educate. In ‘Francophony’, Frenchmen call ‘Enseignant-chercheur’ [researcher teacher] he who is called in ‘Anglophony’, Lecturer (<Lat. legere, “to pick up, to collect through ears, eyes, etc.” and “to read loudly”), “teacher who amasses lot of knowledge from many sources and dictates them to his students”.

Documenting oneself is therefore sum up in research or collection of the best information from the most adequate place and in the exploitation of that are worthy of faith for the greatest profit of science teachers (biblical or not).

Is the ministry of doctor different from the ministry of researcher? I can say no, it’s practically the same profession from or out of the Bible.

TEACHERS WILL BE JUDGED MORE SEVERELY THAN THE OTHER MINISTRIES’ SERVANTS. "Not many of you should presume to be teachers, my brothers, because you know that we who teach will be judged more strictly", James 3:1

Warning!  Do not teach anything you want or you meet.