Commentaries:
In the Parable of the Light recorded in Matthew 5:14-16 (found also in Mark 4:21; Luke 8:16-17; 11:33-36), Jesus Christ uses two figures of speech to express the responsibility of true Christians to influence the world: "a city . . . on a hill" and "a lamp . . . on a lampstand."
Many Judean cities were founded on the summits or sides of mountains, and travelers could see them from afar. Perhaps Jesus pointed to such a city, telling His disciples that they were like it. The city built on an important location can be seen by many eyes over a wide area, representing a disciple's far-ranging and widespread exposure to others.
Jesus' illustration of a shining lamp illuminating the home suggests a disciple's more intimate influence. By design, a Christian's actions cannot be hidden from the eyes of either our families or the world at large. This being the case, he must live a righteous, holy, humble, and pure life, letting his "light so shine before men [and thus] . . . glorify your Father in heaven."
Martin G. Collins
Parable of the Light
"Lamp" (NKJ) or "candle" (KJV) means any portable light, as a lamp, candle, or lantern. Jesus shows the disciples that He had enlightened them so that others might also see the light and benefit from it. When a person lights a lamp, he does not conceal the light but places it where it may be of use. So it is with God's way of life and those who follow it. God gives His truth to us to benefit others. It should not be concealed but show itself in stark contrast to the wicked world, thereby exposing and instructing it. If a light is concealed, as under a basket, no one benefits from it. However, considerate people place a lamp so that its benefits reach all who are in the house.
Martin G. Collins
Parable of the Light
Other Forerunner Commentary entries containing Luke 8:16:
Matthew 5:14-16
Mark 4:21
Luke 8:16-17
Luke 11:33-36
Luke 12:1-7