"The serpent asked the woman, 'Did God really tell you not to eat from any of the trees in the garden?' " (Gn 3:1) Our temptations often come in the form of questions. Also, the issue seems to shift from the sin committed to whether God ever really told us that a particular act was a sin. For example, those advocating the legitimacy of some homosexual acts try to explain that God never really condemned all homosexual acts in the Bible. Next, in temptation, God's commands are often exaggerated. For example, God told Adam and Eve that they could eat of any tree except a certain one. But the devil pretended that God had forbidden eating from any tree.
The devil's next line was: "You certainly will not die! No, God knows well that the moment you eat of it your eyes will be opened and you will be like gods who know what is good and what is bad" (Gn 3:4-5). Here the devil did not merely question, confuse, or misrepresent. He told a bold-faced lie and put an exclamation point on his lie by saying that God was "certainly" lying. In addition to calling God a liar, the devil attributed selfish motives to God. Finally, he told Eve that, if she did not sin, she would deprive herself from reaching her full potential.
The devil is a master-liar, in fact, the "father of lies" (Jn 8:44). We need the Holy Spirit working through the Church, or we will be seduced, confused, used, abused, enslaved, and damned.