For anyone who is still feeding on milk is still unskillful in the Word of Justice; for he is like an infant
Other versions
King James Version
For every one that useth milk is unskilful in the word of righteousness: for he is a babe. English Standard Version
for everyone who lives on milk is unskilled in the word of righteousness, since he is a child.New International Version
Anyone who lives on milk, being still an infant, is not acquainted with the teaching about righteousness.