10 Finally, be strong in the Lord and in his mighty power. 11 Put on the full armor of God, so that you can take your stand against the devil’s schemes. 12 For our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this dark world and against the spiritual forces of evil in the heavenly realms. 13 Therefore put on the full armor of God, so that when the day of evil comes, you may be able to stand your ground, and after you have done everything, to stand. Ephesians 6:11-13
I like how Paul (the author of the book of Ephesians) says “therefore” when saying to put on the armor of God. He’s saying that because there is a battle going on, we NEED to put on the whole armor of God. He’s not saying to do it simply because it’s how God desires for us to live, but he is saying it is necessary based on the situation.