My soul, be on thy guard
And when the devil had ended all the temptation, he departed from him for a season. Luke 4:13
The ESV translates "for a season" as "until an opportune time." I think that is right. It is not just that the devil left our Lord for a time, but that he left him until an opportune moment presented itself. The devil may be evil, but he is not stupid. He will not fire arrows at army tanks. He will attack when he thinks people are weakest: thus, in the wilderness temptation, we are told that it was when our Lord was hungry after 40 days of eating nothing that the devil began to ply his seductions upon Jesus.
Now if the devil attacks Jesus in this way, do you think he is going to be afraid to attack you? And suppose that you have come through a period of temptation without buckling, do you think that he is done with you? No, my friend. He'll be back. He is the Terminator.
This is why the apostle Paul warns us to "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. Wherefore take unto you the whole armor of God, that ye may be able to withstand in the evil day, and having done all, to stand" (Eph. 6:11-13). This is not the work of a moment or of a day. It is the work of a lifetime. Never let your guard down; never become lazy in your walk with Christ.
How do we do this? By being strong in the Lord and in the power of his might (Eph. 6:10). We have heaven's resources at our disposal through Christ. And therefore, let us never weary or become fainthearted. And let us never stop fighting the good fight. As the hymn puts it,
My soul, be on thy guard; ten thousand foes arise; the hosts of sin are pressing hard to draw thee from the skies.
O watch, and fight, and pray; the battle ne'er give o'er; renew it boldly every day, and help divine implore.
Ne'er think the vict'ry won, nor once at ease sit down; the arduous work will not be done till thou hast got the crown.
Fight on, my soul, till death shall bring thee to my God; He'll take thee, at thy parting breath, up to His rest above.