How do we know the armor of God is necessary for Christians?

Ephesians 6:12 emphasizes that Christians wrestle not against flesh and blood but against spiritual forces of evil. This highlights the reality of the spiritual battle that every believer faces. The necessity of the armor comes from an understanding that we are engaged in a fight against deceitful powers that seek to lead us away from Christ. The entire context of Ephesians calls believers to be aware of their enemies and to arm themselves accordingly to stand firm in their faith, making each piece of armor indispensable for spiritual protection and endurance.