Do not make agreements with the enemy

Then about a month after this, Nahash the Ammonite came up and put his forces in position for attacking Jabesh-gilead: and all the men of Jabesh said to Nahash, Make an agreement with us and we will be your servants. And Nahash the Ammonite said to them, I will make an agreement with you on this condition, that all your right eyes are put out; so that I may make it a cause of shame to all Israel.
1 Samuel 11:1-2

And at their words, the spirit of God came on Saul with power, and he became very angry.
1 Samuel 11:6

Saints that make compromises with the world are blind in one eye, unfit to fight the enemy.