Elisha did not take gifts from Naaman.
2 Kings 5:15: When he returned to the man of God with all his company, and came and stood before him, he said, “Behold now, I know that there is no God in all the earth, but in Israel; so please take a present from your servant now.”
Naaman compromised by bowing down to his king.
2 Kings 5:18: In this matter may the Lord pardon your servant: when my master goes into the house of Rimmon to worship there, and he leans on my hand and I bow myself in the house of Rimmon, when I bow myself in the house of Rimmon, the Lord pardon your servant in this matter.”
Greed is Gehazi’s motive and he tells a lie to get some money.
2 Kings 5:22: He said, “All is well. My master has sent me, saying, ‘Behold, just now two young men of the sons of the prophets have come to me from the hill country of Ephraim. Please give them a talent of silver and two changes of clothes.’”
Because Gehazi lied, Elisha said that Naaman’s disease will come to him. Carrying a secret wrong ambition ruined Gehazi’s whole life.