Elisha cursed the children who mocked him at Bethel.
Moab was the incestuous son of Lot, and his descendants were cursed
when they turned their backs on the Israelites coming from Egypt and
also later hired Balaam to curse them. Jesus cursed a fig tree. In
all three instances, the effect of the curse was deadly. Forty-two
children were mauled and killed by two bears, Moab was wiped out by
a three pronged invasion, and the fig tree was dried up from the
roots the next day. God firmly established Elisha as a prophet when
the people of Jericho came to him for help with their drinking
water. It was not the salt, but the power of God that cured the
water. Later the armies of Jehoram and Jehoshaphat ran out of water
when they set out to invade Moab through the wilderness of Edom.
Elisha instructed them to fill the valley with ditches and God
supernaturally supplied the water. The Moabites thought the water
looked like blood and walked into a trap of God's making that culminated in their
death and destruction. God has a spiritual law of sowing and
reaping. Most Christians have not understood that curses are real
and bad things happen when God puts a curse on a person or a nation.