Satan foolishly sought to be like the Most High, and his pride led him to a great fall. The father of lies is the master of telling them, and it is only by being grounded in the word of God we can recognise and avoid falling prey to His deceptions. Satan was able to deceive Eve by first questioning then denying what God had plainly said. For those who can read God's word and have the Holy Spirit within them, blatant lies are not as effective as partial truths--which are still a complete lie. As long as we reside in these bodies of flesh, there is potential we can be swayed by attractive appeals to our flesh.
We see this appeal to fleshly desire in David's men when King Saul pursued David to kill him. While in the wilderness of En-gedi, Saul ventured into the same cave David and his men sheltered in. They urged David to take full advantage of the situation in 1 Samuel 24:4: "Then
the men of David said to him, "This is the day of which the LORD said to you, 'Behold, I will
deliver your enemy into your hand, that you may do to him as it seems good to
you.' " And David arose and secretly cut off a corner of Saul's robe." There were many times in scripture God promised to deliver the enemies of His people into their hand, and it is not clear if God said this in particular to David. But the second part of their statement reeks of sulfur, for they appealed to his flesh. Instead of doing to Saul as seems good according to God's will, they used God's name to encourage David to do his own will. Instead of lopping off Saul's head, he chose to cut off the corner of his king's robe.
So tender was the heart of David that he felt remorse over what he did as it says in 1 Samuel 24:5-6, "Now
it happened afterward that David's heart troubled him because he had cut Saul's
robe. 6 And he said to his
men, "The LORD forbid that I
should do this thing to my master, the LORD'S anointed, to stretch out my hand
against him, seeing he is the anointed of the LORD." David confessed his sin before the men, for in doing as seemed good to him it wholly missed the mark of God's righteousness. David was anointed of God to be king, but since God had not yet removed Saul from the kingdom David was to presently submit to God in faith. Falling for the devil's lies gives us insight into the evil in our own hearts, and the wise learn from error coupled with repentance. As much as David loved and trusted his men, the truth of their words could be discerned by knowledge of God and His word. Appeals to the flesh and encouragement to "do as what seems good to you" ought to be a red flag every time.