2 Kings 2

9 Elisha is not asking for twice the power of Elijah, he is asking to be the "primary heir." When a man left an inheritance to his children, each would get an equal portion, except for the primary heir who received twice as much as the others.
10 But Elijah can not appoint prophets for God. God must choose them. Elijah tells Elisha that if he witnesses Elijah's departure then God has appointed him as heir to the position of "chief prophet."
11 Elijah's heart was so close to God that God took him into heaven without requiring him to die.

Some people mistakenly assert that Elijah was taken up in the chariot, but even a brief reading of the verse indicates that he was carried into God's presence by the whirlwind (or storm).

12 Elisha knew that a godly man had just received a great reward, but he was terribly distressed at the loss of Elijah from the world.
13 Elisha had seen Elijah depart and had received the prophet's mantle. He knew he had inherited the difficult task of being the chief prophet for Israel and so he headed back to begin his work.
14 Elisha uses the phrase, "God of Elijah," but this doesn't mean that he did not believe He was also the "God of Elisha." Elisha knew he was about to experience the power of God in a way he had never known before.
15 It was now obvious to all that God was displaying His power through Elisha just as He had with Elijah. The prophets bowed before Elisha in recognition of his leadership position.
16 Elisha did not die, so there was no body and no grave to visit. The concept of a direct translation from earth to heaven did not make sense to the young prophets so they reasoned that Elisha must still be alive somewhere in the region. Elisha had seen Elijah's ascension and counseled the men to accept it by faith even though they did not understand what had happened.
17 But the other prophets would not believe it and apparently their persistent begging embarrassed Elisha to the point of granting their request. Some people will not believe unless they check things out for themselves. Sometimes this is necessary, but in spiritual matters that God has spoken about, it is best to take Him at His word.
18 Of course, the strong men wasted a lot of time looking for someone Elisha had already told them they would not find. Perhaps we could say that no harm was done, but what work was neglected as 50 men spent three days on a futile search?
19 Jericho had a great location, but had poor water quality. Apparently the water was so bad that when farmers attempted to grow anything, the crops would fail. The word for "unfruitful" here also is used to refer to the miscarriage of a baby.
20 Salt is a symbol of purification and preservation.
21 Perhaps we could reason that the salt killed an organism in the water that caused it to be bad or that the salt changed some chemical problem, but Elisha makes it clear that God's power cleansed the water.
22 If the water had been cleansed merely by the physical characteristics of the salt then we might expect the problem to return once the salt had dissipated. However, the indication here is that the cleansing was permanent, which in turn is an indication of God's power at work.
23 The young boys may have been mere children, but it was obvious they had no respect for their elders or for God's chosen prophet. This may have been a "gang" of unruly boys or they may have been prompted by their parents to insult Elisha. They certainly were mocking Elisha's physical appearance, but some have suggested that the youngsters were mocking Elisha's similarity to Elijah. Elisha had "gone up" in the whirlwind, and they were challenging Elisha to do the same.
24 Apparently there was no hope that these boys would ever repent, so God struck them down at that moment. The bear managed to strike down "only" 42 of the boys.