Similar to typology, illustration identifies the recurring patterns in God’s redemptive plan. There are many instances in the Old Testament when something or someone does not fit the strict definition of a typology. Nevertheless, in that thing, person, or event a consistent pattern exists which helps to illustrate a profound truth about Jesus.
To preach illustration the preacher will use an image, event, or person to bridge to Christ. For example, although Joseph, the son of Jacob, is often preached as a typology one could argue that his life and person do not fit the parameters of a true type. Nevertheless, the life of Joseph is a powerful illustration of the Incarnation and Exaltation of Jesus as described in Philippians 2. Joseph was the favoured son of Jacob, before he was thrown into a well, sold into slavery, and falsely accused and sentenced to jail. Though innocent and obedient, Joseph found himself set low. However, having properly interpreted dreams for the baker and cup bearer of Pharaoh, Joseph was ultimately exalted out of prison when he demystified the dream of Pharaoh himself. Having been condemned to death in prison, Joseph was then given a name above all names in all of Egypt, with the exception of Pharaoh. Seeking food, and in fulfillment of Joseph’s own adolescent dream, his brothers came to his court and bowed their knees, confessing that Joseph was lord over them. This may not be a type, but it is a clever illustration of the pattern of Jesus’ Incarnation according to Philippians 2. For, though Jesus was in the form of God, He did not count equality with God a thing to be grasped, but made Himself nothing, taking the form of a servant, being born in the likeness of men. And being found in human form, He humbled Himself by becoming obedient to the point of death, even death on a cross. Therefore God highly exalted Him and bestowed on Him the name that is above every name, so that at the name of Jesus every knee should bow, in heaven and on earth and under the earth, and every tongue confess that Jesus Chris is Lord to the glory of God the Father (Phil 2:6-11). The preacher can use the life of Joseph as an illustration in order to exhort the congregation to have this same mind among themselves, which is theirs in Christ Jesus.
Illustration invites us to preach powerful patterns that exist in the Bible that may not be strict types. Of course great care must be taken not to bend illustrations too far. Nevertheless, illustration remains an effective tool in the kit of an able preacher.