Rahab's lie
Whether Rahab's deception can be justified by the danger to the spies and is included in the praise of her faith, or is a lie that Scripture records without approving.
Joshua 2:1-7
1Joshua the son of Nun secretly sent two men out of Shittim as spies, saying, “Go, view the land, including Jericho.” They went and came into the house of a prostitute whose name was Rahab, and slept there.
2The king of Jericho was told, “Behold, men of the children of Israel came in here tonight to spy out the land.”
3Jericho’s king sent to Rahab, saying, “Bring out the men who have come to you, who have entered into your house; for they have come to spy out all the land.”
4The woman took the two men and hid them. Then she said, “Yes, the men came to me, but I didn’t know where they came from.
5About the time of the shutting of the gate, when it was dark, the men went out. Where the men went, I don’t know. Pursue them quickly. You may catch up with them.”
6But she had brought them up to the roof, and hidden them under the stalks of flax which she had laid in order on the roof.
7The men pursued them along the way to the fords of the Jordan River. As soon as those who pursued them had gone out, they shut the gate.
Hebrews 11:31
31By faith, Rahab the prostitute didn’t perish with those who were disobedient, having received the spies in peace.
What each tradition says
Rabbinic / Midrashic
No sourced position found. Checked the Jewish Encyclopedia (1905) article "Rahab" — it narrates the deception and extols her conversion but passes no judgment on the lie; Sefaria: Rashi on Joshua 2:4 (Metsudah, CC-BY) glosses the hiding only, Radak on Joshua is not served by the API, and the Zevachim 116b aggadah on Rahab is served only in a CC-BY-NC translation, which the license rules exclude.
Patristic
Clement of Rome recounts that when the king’s men came for the spies, Rahab answered that the two men had come to her but had quickly departed and were gone. In this way, the excerpt says, she did not reveal the spies to them.
Clement of Rome, Letter to the Corinthians (Clement of Rome) — Ante-Nicene Fathers (John Keith trans., ed. Allan Menzies, 1896) — Ch. 12 ("The Rewards of Faith and Hospitality. Rahab")
Catholic
Haydock states that Rahab felt herself authorized by God on this occasion to abandon those upon whom God had declared war. Those people could have derived no benefit from the spies being betrayed to them.
George Leo Haydock, George Haydock's Catholic Bible Commentary (1859) — On Joshua 2:4
Orthodox
No sourced position found. Checked archive.org for a public-domain English Eastern commentary covering Joshua (none located — Cyril's surviving PD translations cover Luke and John; Theophylact/Euthymius lack English translations); no orthodox comment on Rahab's deception found.
Reformed / Protestant
Calvin says that even to assist brethren, consult for their safety, or relieve them, it can never be lawful to lie, because that is contrary to God's nature, and God is truth. Still, Rahab's act is not devoid of the praise of virtue, though not spotlessly pure.
John Calvin, Commentary on Joshua (Calvin Translation Society; Christian Classics Ethereal Library) — On Joshua 2:4-5
Evangelical
Wesley says Rahab's answer was false and therefore unquestionably sinful, even though her intention was good. He adds that, being a heathen, she very probably thought an officious lie was not unlawful.
John Wesley, John Wesley's Notes on the Bible (Wesley Center Online) — On Joshua 2:4