Jehosaphat being a spiritual man wanted to know the will of God, concerning their going to Ramoth Gilead. Ramoth Gilead belonged to Israel by the word of God but Ahab was out of the will of God. The prophet Elijah had previously prophesied evil concerning Ahab.
Ahab had wanted to restore back what materially belonged to them but spiritually he was out of order. Even after Elijah's mount Carmel showdown his heart was not turned to the Lord. The majority of the people had rejected spiritual restoration but wanted material blessings, something of the order today. The people had backslidden with a perpetual backlidding. When a people reject a restoration to God and his word the next thing that follows is Judgment. To get the wider picture let us go to Ezekiel 14:9:
Ezekiel 14:9-11
9 And if the prophet be deceived when he hath spoken a thing, I the
LORD have deceived that prophet, and I will stretch out my hand upon
him, and will destroy him from the midst of my people Israel.
10 And they shall bear the punishment of their iniquity: the
punishment of the prophet shall be even as the punishment of him that
seeketh unto him;
11 That the house of Israel may go no more astray from me, neither be
polluted any more with all their transgressions; but that they may be
my people, and I may be their God, saith the Lord GOD.
The next thing was to bring judgment by sending a spirit of dillusion that they may believe a lie and be damned by it.
2 Thessalonians 2:9-13
9 Even him, whose coming is after the working of Satan with all power
and signs and lying wonders,
10 And with all deceivableness of unrighteousness in them that perish;
because they received not the love of the truth, that they might be
saved.
11 And for this cause God shall send them strong delusion, that they
should believe a lie:
12 That they all might be damned who believed not the truth, but had
pleasure in unrighteousness.
13 But we are bound to give thanks alway to God for you, brethren
beloved of the Lord, because God hath from the beginning chosen you to
salvation through sanctification of the Spirit and belief of the
truth:
The king and people were off the beaten track of the word. The prophets had backslidden. Their spiritual scenario is depicted in Isaiah 30: 8.
Isaiah 30:8-13
8 Now go, write it before them in a table, and note it in a book, that
it may be for the time to come for ever and ever:
9 That this is a rebellious people, lying children, children that will
not hear the law of the LORD:
10 Which say to the seers, See not; and to the prophets, Prophesy not
unto us right things, speak unto us smooth things, prophesy deceits:
11 Get you out of the way, turn aside out of the path, cause the Holy
One of Israel to cease from before us.
12 Wherefore thus saith the Holy One of Israel, Because ye despise
this word, and trust in oppression and perverseness, and stay thereon:
13 Therefore this iniquity shall be to you as a breach ready to fall,
swelling out in a high wall, whose breaking cometh suddenly at an
instant.
Jehosaphat, being a spiritual man, having spiritual discernment had a reason to doubt this group prophecy or revelation. He wanted to here from someone else who did not belong to this ecumenical council of Hebrew prophets under the headship of Zedekiah and under the patronage of Ahab.
He wanted to here someone that was independent from this ecclesiastical hierarchy, not necessary popular in the site of the people or the king.
There was Michaiah son of Imlah who stood true to the council of the almighty. Micaiah was spiritual enough to know that in ages past, true God sent prophets stood with the word of God rebuking kings, their priests and prophets for getting astray from the word.
When the word of the Lord came, by the prophet Micaiah they were prophesying by a spirit of dissilluson, by a lying spirit.
When the word of the Lord came by Micaiah the scenario was thus:
1 Kings 22:19-23
19 And he said, Hear thou therefore the word of the LORD: I saw the
LORD sitting on his throne, and all the host of heaven standing by him
on his right hand and on his left.
20 And the LORD said, Who shall persuade Ahab, that he may go up and
fall at Ramothgilead? And one said on this manner, and another said on
that manner.
21 And there came forth a spirit, and stood before the LORD, and said,
I will persuade him.
22 And the LORD said unto him, Wherewith? And he said, I will go
forth, and I will be a lying spirit in the mouth of all his prophets.
And he said, Thou shalt persuade him, and prevail also: go forth, and
do so.
23 Now therefore, behold, the LORD hath put a lying spirit in the
mouth of all these thy prophets, and the LORD hath spoken evil
concerning thee.
Yet Moses in yonder years had told them to prove all things:
The word of the Lord by the mouth of His servants the prophets had to come to pass. That is the acid test:
Deuteronomy 18:17-22
17 And the LORD said unto me, They have well spoken that which they
have spoken.
18 I will raise them up a Prophet from among their brethren, like unto
thee, and will put my words in his mouth; and he shall speak unto them
all that I shall command him.
19 And it shall come to pass, that whosoever will not hearken unto my
words which he shall speak in my name, I will require it of him.
20 But the prophet, which shall presume to speak a word in my name,
which I have not commanded him to speak, or that shall speak in the
name of other gods, even that prophet shall die.
21 And if thou say in thine heart, How shall we know the word which
the LORD hath not spoken?
22 When a prophet speaketh in the name of the LORD, if the thing
follow not, nor come to pass, that is the thing which the LORD hath
not spoken, but the prophet hath spoken it presumptuously: thou shalt
not be afraid of him.
Here is a group of prophets with thus saith the Lord. Here is one prophet with thus saith the Lord, yet their prophecies were contrary to each other. Here was Jehosaphat a righteous king and here was Ahab an unrighteous king leading Israel, a nation laden with sin to some material prosperity. Here was a group of Hebrew prophets one the side of Ahab prophesying good things to Him. Here was another prophet of doom. Here was Jehosaphat a witness. He was to find out the end of all these prophecies.
At the end of it all the true word prevailed.