"And after this did Jehoshaphat king of Judah join himself with Ahaziah king of Israel, who did very wickedly: And he joined himself with him to make ships to go to Tarshish: and they made the ships in Eziongeber. Then Eliezer the son of Dodavah of Mareshah prophesied against Jehoshaphat, saying, because thou hast joined thyself with Ahaziah, the LORD hath broken thy works. And the ships were broken, that they were not able to go to Tarshish." 2 Chronicles 20:35-37

Jehoshaphat had experienced God in a unique way when God fought for him in the war when he was surrounded by his enemies. Here, we see him forming an alliance with God’s enemies. They enter into a ship building business and all their ships are destroyed and that is the last time we hear of their trade.
God is very clear about unholy alliances. Many believers compromise when it comes to marriage, business, jobs etc. Unholy alliances are unholy and there is no need for us to sugar-coat them with other explanations
God is clear; there is no fellowship between light and darkness. No communion between Christ and the devil.

Let us pray…

God, this day I dedicate anew my mind, body and spirit and declare that they are holy unto you. Deliver me from every unholy alliance known and unknown to me. Order my steps that I may walk in holy ways pleasing and acceptable unto you. Father, I pray that for each unholy alliance, give me the courage, boldness and strength to cut it off. I severe in the spirit every alliances that I have that are unholy and this day I commit myself to holy alliances only in Jesus Mighty Name, Amen.