What does Luke 8:16 mean?
This verse can be interpreted multiple ways.It may be that the "light," like the "seed" in the parable of the sower, represents the Word of God. Jesus doesn't teach because He likes the sound of His own voice. He speaks because His audience needs His words, and they should take the responsibility to listen carefully and allow the words to influence their lives. We need to be careful how we hear so we grow in wisdom (Luke 8:18). In this interpretation, Luke 8:17 means that God's truth will be revealed even to those foolish enough to ignore it during their lives on earth.
Some, however, believe "light" parallels the "fruit" of Luke 8:15: the natural results of hearing Jesus' words and living them out, much like Matthew 5:14–16. If this is the case, Luke 8:17 means that our actions inevitably reveal our relationship with Christ. It implies that we act out of what we believe about Jesus.
The parable more closely resembles Mark's extended version (Mark 4:21–25) and Matthew's parable was given at a different time and place. So, the comparison to seed is more likely. There's obvious truth in the idea that sincere believers ought to "let their light shine" (Matthew 5:16) based on their relationship with Christ. Yet the meaning of Luke's verses seems to be that listeners are to be like the good soil, accept the seed, and produce fruit (Luke 8:8). In the same way, people are to "enter" and "see the light," working hard to understand the truth and application of Jesus' teaching (Luke 8:18). Jesus says something similar in Luke 11:33.