TEACHERS ARE HELD TO ACCOUNT BY GOD

Here are some tough words from the prophet Hosea (Chapter 4) to the "children of Israel" AND, in particular, Israel's priests: 

1 Hear the word of the Lord, O children of Israel,
for the Lord has a controversy with the inhabitants of the land.
There is no faithfulness or steadfast love,
and no knowledge of God in the land;
2 there is swearing, lying, murder, stealing, and committing adultery;
they break all bounds, and bloodshed follows bloodshed.
3 Therefore the land mourns,
and all who dwell in it languish,
 and also the beasts of the field
and the birds of the heavens,
and even the fish of the sea are taken away.
4 Yet let no one contend,
and let none accuse,
for with you is my contention, O priest. 
5 You shall stumble by day;
the prophet also shall stumble with you by night;
and I will destroy your mother. [Meaning Israel]
6 My people are destroyed for lack of knowledge;
because you have rejected knowledge,
I reject you from being a priest to me.
And since you have forgotten the law of your God,
I also will forget your children.

The priests are meant to function as the intermediaries between God and humanity. When they lose interest in the knowledge of God, the results are catastrophic. 

With nobody offering to teach the people about the knowledge of God, the people's faithfulness and love begin to fail and they descend into debauchery of all sorts. 

Those in leadership among God's people, Old Testament and New, are held to account for their own attention to the Lord and their ability to pass along truth to God's people. 

A teacher does not need to be a FALSE teacher to be blameworthy in God's sight.

Gulp!

SPIRITUAL STAGNATION IS EVIDENCE OF IGNORANCE

After the Apostle Paul holds Epaphras up as an effective teacher of the Colossians - evidenced by the fact that the gospel was bearing fruit in their lives and increasing - Paul goes on to connect spiritual education directly to life growth two more times in the first chapter of his letter. 

First in verses 9 and 10:

9 And so, from the day we heard, we have not ceased to pray for you, asking that you may be filled with the knowledge of his will in all spiritual wisdom and understanding, 10 so as to walk in a manner worthy of the Lord, fully pleasing to him: bearing fruit in every good work and increasing in the knowledge of God ...

And then later in verses 28 and 29:

28 [Christ] we proclaim, warning everyone and teaching everyone with all wisdom, that we may present everyone mature in Christ. 29 For this I toil, struggling with all his energy that he powerfully works within me.

The first instance highlights the believers' obligation to learn on their own, presumably with the aid of the Holy Spirit. Paul says he prays they will be filled with knowledge of God's will "in all spiritual wisdom and understanding".

The result will be believers walking in a manner worthy of the Lord, defined as "bearing fruit in every good work and increasing in the knowledge of God". 

It's notable that Paul maintains that as the Colossians walk in the knowledge they have already received, they will receive more knowledge. 

The second instance highlights Paul's prerogative as a teacher to warn and teach "everyone", again with the goal of maturity in Christ. 

Whether learning occurs independently or under a teacher, the predictable result is spiritual growth, fruit, and maturity.  

If this can be reverse engineered, then we can say stagnation, lack of fruit, and immaturity - either on the individual or congregational level - is evidence of a lack of learning, both independently and under another's teaching.