The word “instruct” in this sense comes from the concept of sounding down, thus resounding in the ears. It carries the meaning of oral instructions or teaching by word of mouth.
Paul uses this word to call out those who are abusing the Spiritual gift of speaking in tongues in 1 Corinthians 14:19. He states that he would rather speak five words with the mind so that he may verbally instruct others than ten thousand without the mind. The issue with speaking in tongues is that the mind of the one speaking does not comprehend what is spoken (1 Corinthians 14:14—my mind is unfruitful). Since speaking in tongues was a sign to the unbelieving Jews, it is no longer an active gift in the Church today (1 Corinthians 14:22). Now that God is not dealing with Israel as a nation, because the Gentiles are being brought in to share in the blessings of Christ, the gift of speaking in tongues has cause itself to cease; it is not longer of any value to the Church (1 Corinthians 13:8). However, even when it was active, it was never for the purpose of edification or Spiritual enlightenment (1 Corinthians 14:4).
In the opening paragraph of the letter Luke wrote to Theophilus (the friend of God), he employs the concept of verbal instructions received. He writes to put in chronological order the things Theophilus was orally taught (Luke 1:4).
Apollos, a jew from Alexandria, was orally taught in the way of the Lord. He was fervent in spirit and accurately taught the things of the Lord. His teaching, though, was only in the immersion from John the Baptist (Acts 18:25). He spoke boldly in the synagogues concerning what he was taught. Aquila and Pricilla, who had spent a long time with Paul, took Apollos aside and explained the way of God more accurately. Later, Apollos became the pastor of the Corinthian assembly until he grew fed up with their carnality and moved on.
The Jews in Jerusalem had been orally taught about Paul’s time among the Gentiles. These Jews orally taught the Jews in Jerusalem that Paul was teaching that the Jews among the Gentiles should no longer circumcise their children nor follow the way of Moses (Acts 21:20). To correct this, some of the apostles and elders in Jerusalem instructed Paul to take four men who were under a Nazarite vow and pay their expenses so they could shave their heads. This would be done to orally teach the Christians in Jerusalem that Paul carefully followed in the steps of the law (Acts 21:24).
In Galatians 6:6, the NKJV translates the word as “teach” to emphasize what is passed on orally. Unlike general teaching, which can be oral or written, “instruct” here focuses on learning through hearing.
