1 Kings 18:12
And it shall come to pass, as soon as I am gone from thee, that the Spirit of the LORD shall carry thee whither I know not; and so when I come and tell Ahab, and he cannot find thee, he shall slay me: but I thy servant fear the LORD from my youth.
The verse belongs to Elijah's ministry during Israel's idolatry and famine, when he warned the nation. That ministry included standing alone for God on Mount Carmel, where faith overthrew idolatry, followed by the return of rain testifying to the blessings awaiting Israel. Obadiah feared that as soon as he left Elijah, the Spirit of the Lord would carry Elijah to a place unknown to him, so that when he told Ahab and Ahab could not find Elijah, Ahab would kill him.
His fear reflected the fact that Ahab had searched widely for Elijah and punished kingdoms that claimed not to know where he was. In the verse Obadiah declares that he has feared and reverenced the Lord from his youth. He had maintained that reverence while serving under Ahab, even amid the danger from Ahab and Jezebel's persecution of the prophets.
He had proved that reverence by risking his own life to protect God's prophets, even while fearing for his life. Elijah answered Obadiah's fear by assuring him that he would show himself to Ahab that day. Later in that same ministry, Elijah fled Jezebel's threats in weariness, weakness and loss of faith, cutting short the work he had begun so that God appointed another prophet to complete it.