While we relate to our heavenly Father as someone who loves us, created us, and desires to bless us, He is also King. It is as a King that he calls us to battle, representing ourselves as witnesses of Him, possibly even to death, as were the martyrs of Revelation 6. If we die with Him, we will live with Him; if we suffer with Him, we will rule with Him. Check out this weeks sermon by elder Scott Moore "Avinu Malkeinu".