'Teaching' in the Bible

Whom we are preaching; guiding and teaching every man in all wisdom, so that every man may be complete in Christ;

Rooted and based together in him, strong in the faith which the teaching gave you, giving praise to God at all times.

(Rules which are all to come to an end with their use) after the orders and teaching of men?

Let the word of Christ be in you in all wealth of wisdom; teaching and helping one another with songs of praise and holy words, making melody to God with grace in your hearts.