Who said, "What I have written, I have written"?
Who is Elijah's successor?
Who said, "Whatever they build, if even a fox goes up on it, he will break down their stone wall"?
Who walked with God and was not?
Who hid the two spies in Jericho?
Now look at your five answers, and tell me what name is found in the acrostic?
Have fun!

Thanks for being sporting, everyone. Hope we all learn from one another.

Hi there, sister Strawberry. Thanks for having a teachable heart. That's what matters to God.
As for your question, an acrostic is a poem in which special letters spell another word. These letters usually appear at the beginning of each line. You can read more about it here:
http://www.holycross.edu/departments/socant/dhummon/acrostics/what_is_acrostic.html
While we are on this topic, here's sharing what I learnt in church about an acrostic that really happened in the Bible. Remember Pilate wrote "Jesus of Nazareth, The King of the Jews" in Hebrew, Greek and Latin, and put it on the cross? Well, in Hebrew, it reads "YESHUA HANOZRI WUMELECH HAIEHUDIM"
When read in acrostic, it would be:
Yeshua
Hanozri
Wumelech
Haiehudim
YHWH is the name of our covenant-keeping God. Literally, Jesus was declared to be YHWH (or Yahweh) at the cross! No wonder the chief priests asked Pilate to change the title. But Pilate said, "What I have written, I have written", thus fulfilling God's plan.