{Without experience} (apeiros). Old adjective (alpha
privative and peira, trial). Inexperienced. The babe (
(8870)ios,
old word, negative 
(885c) and epos, word like Latin _infans_,
infant, not able to talk), not able to chew if one uses only milk
and is without teeth. Perhaps moral truth is meant by "word of
righteousness" (cf.  1:2  2:3  for the word spoken by Christ).