JMNT(i)
12 For also, being indebted (or: obligated) to be teachers, because of the time [gone by], you again have a need of someone to be teaching you folks the elementary things (or: fundamental principles; rudiments and rules) of the beginning of the brief spoken words (or: principle short thoughts and messages) of God, and you have become folks having need of milk, and not solid food.
13 For everyone partaking (sharing in) milk [is] untried (inexperienced) pertaining to [the] Word of the Way pointed out (from the message of fair and equitable dealing or an idea about rightwised relationships; also: = in regard to the idea of, and the reason derived from, covenant membership), for he is a babe (a non-speaking infant, or one who is still childish and unfit to bear weapons).