When Jesus died on the cross, where did His Spirit go? Some say He descended into Hell, but surely that can't be. He went into the Lake of Fire, right?
Regarding the death of Christ, scripture teaches that Jesus visited Hell and preached to the spirits now in prison (1Pet 3:19). Upon His resurrection, Jesus led free captives after his crucifixion (Eph 4:8-10).
To understand these verses, we must first understand the nature of the place called "hell" according to scripture. According to Luke 16, the holding place of the dead prior to Christ's death and resurrection was called Sheol. Sheol is the Old Testament name for the place all human spirits (or souls) were kept after the death of the body.
Sheol consists of two parts or halves. On one side of Sheol is a place of comfort, while the other side of Sheol is a place of torment. The side of comfort is reserved for the saints (i.e., those saved by faith), while the side of torment holds the souls of all unbelievers.
The Bible calls the side of bliss "Abraham's Bosom," a euphemism reflecting the Bible's teaching that Abraham is the father of all who believe (Rom 4:11). Meanwhile, the side of torment is called Hades (or Ghenna in Hebrew), from which we get the English word hell.
Prior to Christ's death, all departed souls existed in Sheol, either in Abraham's Bosom or in Hades. Such an arrangement was made necessary
As you correctly imply, Hell is not the Lake of Fire. It is a place the Old Testament calls Sheol. There are many references to this place in the Old Testaments, including Num 16:33, 1Sam 2:6. This place is described in greater detail by Jesus in Luke 16 in the story of Lazarus and the rich man.
For a complete teaching on this lesson, please listen to Lesson 16B of our Gospel of Luke study. In addition, we recommend you listen to Lessons 20D from our Revelation study for a complete explanation of the differences between Hell and the Lake of Fire.