Until called to the throne at the age of thirty-five, Jehoshaphat had before him the example of good King Asa, who in nearly every crisis had done "that which was right in the eyes of the Lord." 1 Kings 15:11. During a prosperous reign of twenty-five years, Jehoshaphat sought to walk "in all the ways of Asa his father; he turned not aside." In his efforts to rule wisely, Jehoshaphat endeavored to persuade his subjects to take a firm stand against idolatrous practices. Many of the people in his realm "offered and burnt incense yet in the high places." 1 Kings 22:43. The king did not at once destroy these shrines; but from the beginning he tried to safeguard Judah from the sins characterizing the northern kingdom under the rule of Ahab, of whom he was a contemporary for many years. Jehoshaphat himself was loyal to God. He "sought not unto Baalim; 191 but sought to the Lord God of his father, and walked in His commandments, and not after the doings of Israel." Because of his integrity, the Lord was with him, and "stablished the kingdom in his hand." 2 Chronicles 17:3-5.

Før Josafat blev konge i en alder af fem og tredive år, havde han haft et forbillede i den gode kong Asa, som i næsten alle krisesituationer havde gjort, "hvad der var ret i Herrens øjne". 1Kong. 15,11. Josafat "vandrede nøje i sin fader Asas spor og veg ikke derfra" i de fem og tyve fremgangsrige år, han regerede. Josafat bestræbte sig på at styre riget klogt og forsøgte derfor at overtale sine undersåtter til at afholde sig fuldstændig fra afgudsdyrkelse. Der var dog mange, der "blev ved at ofre og tænde offerild på højene". 1Kong. 22,43. Kongen ødelagde ikke disse offersteder på engang, men søgte fra første færd at beskytte Juda imod de synder, som var mest fremtrædne i nordriget på Akabs tid. Josafat var i mange år konge samtidig med Akab. Personligt var Josafat tro over for Gud. Han "søgte ikke hen til baalerne, men til sin faders Gud og fulgte hans bud og gjorde ikke som Israel". Takket være denne troskab var Herren med ham og grundfæstede "kongedømmet i hans hånd". 2Krøn. 17,3-5.