Revelations 12:10 describes Satan as the "accuser of the brethren." The ministry of the Lord is reconciliation the ministry of Satan is accusation. So when we say as Joshua said "as for me and my house we will serve the Lord," we are saying we will not join Satan in speaking judgment and condemnation towards our fellow Christians but rather do everything in our power to reconcile them to God.
Paul was constantly facing accusations by the Chief Priests and Jewish leaders, which is the theme of Acts 25. They brought their case to the newly elected governor Festus, they tried to trick him to send Paul to Jerusalem in which they would set an ambush to kill him. Festus told them no you all can accuse him in Caesarea. Paul defended himself, claiming he had done no wrong. Festus wanted to do the Jews a favor so he asked Paul if he was willing to defend himself in Jerusalem. Paul knew his fate if he did and said, "no, I appeal to Ceasar." So the case would now go to the highest court. King Agrippa and Bernice visited Festus in which he asked them for advice because he found no fault with Paul and didn't know how to even address the appeal to Ceasar. They now wanted to hear from Paul themselves.
When we have discerned the will of God then we now can walk in wisdom regarding the battles we face in between the fulfillment. Being prudent is gaining the grace to know what to say and when to say it. We can trust God that He will grant us favor and protect us from our enemies if we just stay on His path. The enemy will do everything he can to prevent us from reaching our destination so we must assure we do not abort the process, but fearlessly proceed forward, cautiously, but confidently, like Jesus, confessing, "not my will, but yours, Oh Lord!
Paul knew his purpose was to speak before Ceasar and so each governor or king was a stepping stone to the ultimate audience of the highest position in the known world. He spoke whatever was necessary, he wasn't trying to gain his freedom, he was already free within, his focus was God's will, and he knew that no matter what others had planned for him, God would intervene and make a way for him to complete His final assignment.