Satan does this to try to hinder the work of God on earth. He discourages unity among believers and he encourages Christians to ignore the Word and accept false teaching so that they will revert to their former manner of life. He tempts the believer with an improper emphasis on details of life such as money, success, social life, pleasure, loved ones, health, sex, materialistic things, or status symbols. The mature believer knows that his happiness is not derived from these things, so he is not a slave to them. The novice Christian, however, may try to gain happiness from such things, and this will distract him from the Word of God.
False teaching is also a part of Satan's strategy.
There are three categories of the will of God which Satan tries to interdict. Satan encourages believers to worry. Worry neutralizes the soul of the believer. One of the functions of the Faith-Rest principle is to protect the Christian in the area of having a proper focus on life. Satan also promotes heavily in the area of mental attitude sins such as fear, worry, bitterness, desires for revenge, pride, guilt feelings, lack of love, failure to forgive, hatred, mental adultery, and so forth.