The Battles within and without

For though we walk in the flesh, we do not war after the flesh: [4] (For the weapons of our warfare are not carnal, but mighty through God to the pulling down of strong holds;) [5] Casting down imaginations, and every high thing that exalteth itself against the knowledge of God, and bringing into captivity every thought to the obedience of Christ; [6] And having in a readiness to revenge all disobedience, when your obedience is fulfilled.

2 Corinthians 10:3-6 KJV

The entire bible, from the beginning of Genesis to Revelation,  is about battles and survival. For each battle, there are guidelines on how to confront and overcome.  Sometimes the scripture says "beware". In such situations, being aware is the strategy. 

Somewhere else the bible would says "bind and loose". In another, it would say "fight a good fight". In another, it would recognize that you cannot fight alone. In such cases, it would say whatever two or three agree as touching any matter, it shall be done, Matthew 18:19. Here, alliances are formed.Nations form allies, because they want to limit individual casualties and share the victory, so it is in some battles we face.