The shield

"Finally, be strong in the Lord and in the strength of his might. Put on the whole armor of God, that you may be able to stand against the schemes of the devil. For we do not wrestle against flesh and blood, but against the rulers, against the authorities, against the cosmic powers over this present darkness, against the spiritual forces of evil in the heavenly places. Therefore take up the whole armor of God, that you may be able to withstand in the evil day, and having done all, to stand firm. Stand therefore, having fastened on the belt of truth, and having put on the breastplate of righteousness, and, as shoes for your feet, having put on the readiness given by the gospel of peace. In all circumstances take up the shield of faith, with which you can extinguish all the flaming darts of the evil one; and take the helmet of salvation, and the sword of the Spirit, which is the word of God, praying at all times in the Spirit, with all prayer and supplication." -Ephesians 6:10-18

When I read this last summer (I think), I was struck that Paul said "in every circumstance" to take up your shield of faith. That should be my instinct whenever something comes up, good or ill. The evil one is on the prowl even in the happy times (like at a birthday party), and we must be ready with our shield to deflect the darts (judgmental or jealous thoughts). I think it's amazing that God has given this weapon--simple faith in Him--that will enable us to "extinguish all the flaming darts of the evil one". 

Raise your shields, one and all.