In the psalmist' days, whenever people travel from one place to another in the night, they bring along a lamp, with a lit candle inside it.
Light from such a lamp illuminates the path ahead just enough for the person to take the next step. They may not be able to see their end destination, but they trust that every step they take will lead them to the place they desire to go. The light will reveal near potential dangers in their path to avoid.
As Christians, since we "walk by faith and not by sight" (2 Corinthians 5:7), we may only be limited to see several steps ahead. But it is all the more vital to have faith.
Hold on to the lamp that is God's Word and His promises. Avoid the dangers and traps of the enemy. Let His Word be the lamp to your feet; a light to your path in every season.