Whenever an emergency arises, whenever you find yourself under extreme pressure, you will always do what you have trained yourself to do.
You will not say, “Oh, I shouldn’t take the time to pick up these casings right now. There are bad guys out there trying to kill me so I need to reload as quickly as possible.” You will simply do what you have always done. It’s why schools and workplaces run fire drills, why the flight attendants tell you how to operate those dangling masks every time you get on a plane, and why the various branches of the armed forces run drills over and over and over.
Why is it important to memorize scriptures, to sing hymns during the day, to talk to God as if He were right there with you all day long? Why is it important to train yourself not to use foul language even when no one else is around, not to lose your temper over even the smallest matters, not to develop dependencies other than God when you are feeling down, not to return evil for evil, even when you are just driving down the road? Because when life’s pressures rise, you will do what you practice.
If you curse in private, you will curse for all to hear; but if you pray at the drop of a hat whenever something does not go well, that is what you will do instead. If you have trained yourself to turn the other cheek at the least little grievance, you will more easily do so with the larger ones. If you have filled yourself with the scriptures, those precious words will spring to mind and bail you out of temptation.
In case of emergency, you will do what you have trained yourself to do. Is it time for a spiritual fire drill?
With my whole heart have I sought you: Oh let me not wander from your commandments.
Your word have I laid up in my heart, that I might not sin against you.
Blessed art thou, O Jehovah: Teach me your statutes.
With my lips have I declared all the ordinances of your mouth.
I have rejoiced in the way of your testimonies, As much as in all riches.
I will meditate on your precepts, and have respect unto your ways.
I will delight myself in your statutes: I will not forget your word. Psalm 119:10-16