holding fast the faithful word which is in accordance with the teaching, so that he will be able both to exhort in sound doctrine and to refute those who contradict.
Titus 1:9 (emphasis mine)

In the previous article we addressed the need for the elder to be well-versed in the Scriptures. He needs to know his theology for his personal growth and also for his ministry. One of his responsibilities as an elder is “to exhort in sound doctrine.”

But as for you, speak the things which are fitting for sound doctrine.
Titus 2:1

Not all elders will be able to teach at the same level (1 Timothy 5:17), but all elders must be capable of earnestly communicating sound doctrine. This necessitates that they have the critical knowledge to fulfill this task. Far too many churches place the sole responsibility for speaking sound doctrine on the shoulders of the teaching pastor. In fact, most churches only require a potential elder to affirm the doctrinal statement of the church. There is no process to be certain that he is able to personally communicate sound doctrine.

The lack of theological training for all the elders has put the church at great risk. Having a plurality of well-equipped elders is essential for the spiritual health of the church. This means that churches must think carefully about how to equip godly men to become elders in the church. They must also consider how to test them to make sure they can fulfill this most critical role.