If I were the Devil, I would consider myself to basically have two problems: (1) How I could keep control of people in general, and how I might ensnare the Christian?
If I were the Devil, the very first thing I would do would be to discredit the inspiration, perfection, and authority of the Scriptures. I would do my best to find an argument that would keep people from accepting these as attributes of the Scriptures. Perhaps I could do so through your schooling, your friends, the music to which you listen, or through the published materials which you read. However, I would not dare to show you 2 Timothy 3:16; James 1:25; or 1 Corinthians 4:6 and 2 John 9. For should you read these you could believe that all Scripture came by inspiration of God, that it is a perfect law, and that you were to be limited in teaching and practice by those Scriptures. Thus, I might fail here, but I would not give up.
Next, if I were the Devil I would try to persuade you that you had plenty of time to obey the gospel, that you had some things that you could and should enjoy before you settle down to become a Christian. Of course if you managed to read 2 Corinthians 6:2 or Hebrews 3:15, you could see things a little differently. Then, should you happen to read the examples of conversion in Acts of the Apostles you would immediately see the urgency in obeying the gospel. So, again I might fail, but I would not quit.
Should you really believe the Scriptures and knew that you should obey in haste, I would point out how difficult it would be for you to live the life of a Christian. You just couldn’t do it, I would point out. Look at all those who are trying and how far short they fall; you would not wish to be a hypocrite in such an effort. If some truly concerned Christian should have you read Galatians 6:2, you would know that you would have the help of fellow Christians. To make matters worse for me, some of those same Christians might have you read 1 Corinthians 10:13. I could see failure of my efforts here, because you would realize that you had the assistance of the Almighty.
If I were the Devil, I would wish to ensnare the Christian, thus weaken or destroy the influence of the church (Eph 3:10). I would say forget the church and live it up, live for the day, and when in Rome do as the Romans do. Life is too short to be serving such a hard gospel and a difficult God (Rom 11:22 f; 2 Tim 3:12). I would encourage Christians to forsake God and to live life to its fullest (Heb 10:25). I would tell Christians it is a waste of time to put on the whole armor of God (Eph 6:11-18). I would encourage Christians to use the vices of the world in order to get ahead (1 Jn 2:15,16). I would suggest that they be greedy and keep their wealth to themselves and for themselves (Gal 6:10). However, I would be very careful that they did not read 1 Thessalonians 5:22 or Romans 12:2, especially if they were really honest, just in case you would see something wrong with my reasoning. Then, if you should read Ephesians 5:6 and you really wanted to reach heaven, you would want no part of my advice. This is all true because, you see, my success depends greatly upon your cooperating with me and how ignorant of the scriptures you truly are (Acts 17:11). After all, if you knew the scriptures, you would know that I am the father of all liars and a murderer from the beginning of time (Jn 8:44). If you knew me, you would know I am searching the world for whom I may devour (1 Pet 5:8) If you knew me, you would know I impersonate angels of light and sit among you as you worship God (2 Cor 11:13-15). If you knew me, you would know I seek to deceive the world in order that the world share hell with me (Rev 12:9). Beware of his false teachers for they are many (1 Jn 4:1).