If Jesus, after being with his disciples almost continuously for three whole years, found that they took a long time to understand his teaching, we should not be surprised when progress is slow in our attempts to disciple people. ..... We musn't get discouraged when those we disciple act in ways that seem to betray all that we have taught them. We must persevere in teaching them the Word, knowing that this is what will ultimately effect a change in their thinking and attitudes.

Ajith Fernando, Jesus Driven Ministry, Chapter 10