"Be sober, be vigilant; because your adversary the devil, as a roaring lion, walketh about, seeking whom he may devour (1 Peter 5:8). To be sober is to be mentally self-controlled. One must be careful of what he attends to. What's on your mind? Remember your thoughts end up guiding your words and actions. To be vigilant is to be always alert. "Ponder the path of thy feet, and let all thy ways be established (proverbs 4:26). Is your mind thinking on the things of God, or Is your mind on the things of this world? There are so many things that can make you loose focus, cause anxiety, depression, and the like.
Don't Worry
"And ye shall hear of wars and rumors of wars: see that ye be not troubled: for all these things must come to pass, but the end is not yet (Mathew 24:6). Be careful for nothing; but in every thing by prayer and supplication with thanksgiving let your requests be made known unto God. And the peace of God, which passeth all understanding, shall keep your hearts and minds through Christ Jesus (Philippians 4:6-7)
Think
Let the Truth of the Gospel of Jesus Christ be the object of your Faith. No other Gospel. "Put on the whole armor of God, that ye may be able to stand against the wiles of the devil. For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places (Ephesians 6:11-12). Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things (Philippians 4:8).
Jesus Said..
"I will not leave you comfortless: I will come to you (John 14:18).