"..a time of war."

 It begins. See here

"There is an appointed time for everything, and a time for every affair under the heavens. A time to give birth, and a time to die; a time to plant, and a time to uproot the plant. A time to kill, and a time to heal; a time to tear down, and a time to build. A time to weep, and a time to laugh; a time to mourn, and a time to dance.A time to scatter stones, and a time to gather them; a time to embrace, and a time to be far from embraces. A time to seek, and a time to lose; a time to keep, and a time to cast away. A time to rend, and a time to sew; a time to be silent, and a time to speak. A time to love, and a time to hate; a time of war, and a time of peace."

Ecclesiastes 3: 1-8.

Saintly perspectives on just war emphasize that while peace is the ultimate goal, force may be used as a last resort to defend justice and the common good. 

Saint Augustine of Hippo emphasized that war should be waged to achieve peace, not for violence or revenge.

Saint Thomas Aquinas outlined that a just war requires sovereign authority, a just cause, and a rightful intention.

Saint Bernard of Clairvaux: Suggested that while not ideal, sometimes it is necessary to stop persecution.

Saint Athanasius & St. Basil noted that killing in defense of the faithful and piety is not considered murder, but a necessary action.

Saint Isidore of Seville: Defined just wars as those waged only for defense or to stop an enemy.