Eph 6:10 Finally, my brethren, be strong in the Lord and in the power of His might.
The book of Ephesians is broken into two sections, the 1st 3 chapters tackles right believing (doctrine), the last 3 deals with right living (practice). The right living is not possible alone when enemies are present. As the apostle Paul saw forces arising, his final words encourage us to be strong, stand firm in the faith in His power. Believers are secure and will be triumphant only as they make the strength of God their own. The strength of every saint lies in the Lord of hosts. God can overcome His enemies without our help, but we cannot shield ourselves without His arm.
As a soldier of the Lord, you are not equipped for war until you have put on the armor which is followed by, “…having done all, to stand.” and see the salvation of the Lord. All the dressing without taking the shield makes you defenseless against assaults, you must vs.16, “above all taking the shield of faith with which you will be able to quench all the fiery darts of the wicked one”
In buying a car, safety is a priority over all gadgets. Assurance that God is present to protect us is our shield of faith. “He only is my rock and my salvation; He is my defense; I shall not be greatly moved”, (Psa 62:2). To wake up realizing you have a shield is comforting, He urges us to realize that He will consistently be with us.