Earlier we pointed to Jesus' statement that "every good tree bears good fruit, but the rotten tree bears bad fruit," noting that good teaching results in good character (Matt. 7:17). "It's not the only way to assess doctrine," we said, but it is one important measure. But before we look at the lives of other people, we must first inspect our own hearts. Jesus said: "If anyone's will is to do God's will, he will know whether the teaching is from God or whether I am speaking on my own authority" (John 7:17). If our motivation is anything other than a sincere desire to please God, we certainly are not prepared to evaluate teaching by anyone.

Evaluating a teaching means asking not only "Is it true?" but also "Is it important?" Some doctrines are of "first importance," while others count for far less (1 Cor. 15:1ff). Discerning a teaching's truth and importance involves comparing it with the Scriptures -- prayerfully and in context. The reality is that we all have our own prejudices, ignorances, and internal grids, through which we habitually filter new information. It is therefore wise to search the Scriptures in company with other believers (preferably not only those who are just like us), to state our findings with humility and with grace, and to remain open to correction and further light.

But there is no cause for despair; the greater the truth, the more confident we may be that God himself will guide us in the task of discernment. For example, Jesus' true identity is not known by human reasoning but by divine revelation (Matt. 16:16-17; Lk. 10:22). As we "consider," God gives discernment (2 Tim. 2:7). For those who are part of the community of faith, the Holy Spirit is the ultimate teacher (1 John 2:26-27).