Just for general information. There is a thread on lying and I did not respond to it.
Lying and trickery in the Old Testament and in Middle Eastern culture. It is actually a pretty deep topic.
First off as for as Rahab and her deception.
Rahab was a prostitute and and some believe even a medium...seer, because of what she said about knowing that Yahweh had given them the land. Her name also appears in the Bible and Jewish folklore as a dragon. References to this in the scriptures are Psalms 87:4, Psalms 89:10, and Isaiah 51:9
Rahab worked with Joshua's men...in his effort to conquer the city of Jericho as was directed by God Himself. You may have heard that Yeshua's name was a very common name in His time period and the Old Testament ....that is true. Joshua is a mistranslation.....No "J's" in the scriptures, Old or New Testament. His actual name was Yeshua.
Rahab hid Joshua's men and lied to the king. She made an agreement with Joshua's men that if she helped them that she and her family would be saved. Was that wrong? No, for a few reasons.
The Bible makes it clear that she is a believer in Yahweh as she is in awe of Him. So she was justified by both Faith and Good Deeds. James seemed to agree with this...in James 2:24-25, she was used as an example; "You see that a man is justified by works and not by faith alone. In the same way, was not Rahab the harlot also justified by works when she received the messengers and sent them out by another way?" ....and since she also believed in Yahweh, it was also a matter of faith. As it also appears she had an interest in changing her ways and joining the Israelites.
So in the end after Jericho fell to the army of Yeshua, Rahab and her whole family were preserved according to the promise of the spies, and she joined the Israelite people. She married Salmon of the Israelite Tribe of Judah and was the mother of Boaz. Christ also belonged to the Tribe of Judah. Salmon is listed in the bloodline of Christ, so Rahab is also in that bloodline as was her son Boaz. So it appears that Rahab found favor with Yahweh. According to the Talmud she repented of her sins.
Now as far as lying. Technically the Bible denounces lying...there is also bearing a false witness against those that are accused of wrong doing. The function of the Law was dependent upon the honesty of witnesses, but there is more details to that....in practice it is a matter of intent. In this time period as is today in the Middle East, trickery can be considered as a form of intelligence....sounds weird? Yahweh said, Jacob I loved, but Esau I hated. Jacob used trickery to best Esau and Laban and David and Hercules used trickery. Abraham was considered righteous but he would deceive people by saying Sarah was only his sister. (Which she was his half sister, but she was also his wife.) It is a topic, being smart enough to outwit someone. And it is a cultural thing even today in the Middle East. As a military person I can tell you that trickery is often used as a strategy. As a historian, I can tell you that trickery has been used in a lot ancient battles.
Christians have been taught to be honest and overall I agree. But if you always tell the truth anybody can pry into your personal life and you are obliged to answer truthfully. Not answering can be an answer.
Putting it into another perspective....we should not deceive for personal gain or benefit. Keeping a birthday party a secret or a gift a secret does not count. I do not even call it a white lie. Telling someone that is buying your car that you know of no issues....when you do know there are issues....is a lie. People have to use their own conscience on such matters.