And before they were laid down,.... Under the stalks of the flax; or rather, since they are said to be hid in them, before they were fallen asleep, so Kimchi and Abarbinel:

she came up unto them upon the roof; to acquaint them how things were, and to converse with them on the following subjects.

Notwithstanding these precautions, the men escaped. As soon as the officers had left Rahab's house, she went to the spies, who were concealed upon the roof, before they had lain down to sleep, which they were probably about to do upon the roof, - a thing of frequent occurrence in the East in summer time, - and confessed to them all that she believed and knew, namely, that God had given the land to the Israelites, and that the dread of them had fallen upon the Canaanites ("us," in contrast with "you," the Israelites, signifies the Canaanites generally, and not merely the inhabitants of Jericho), and despair had seized upon all the inhabitants of the land. The description of the despair of the Canaanites (Joshua 2:9) is connected, so far as the expressions are concerned, with Exodus 15:15 and Exodus 15:16, to show that what Moses and the Israelites had sung after crossing the Red Sea was now fulfilled, that the Lord had fulfilled His promise (Exodus 23:27 compared with Deuteronomy 2:25 and Deuteronomy 11:25), and had put fear and dread upon the Canaanites.

And before they were laid down, she came up unto them upon the roof;

2:8 Laid down - To sleep as they intended.

Jos 2:8-21. The Covenant between Her and Them.

8-13. she came up unto them upon the roof and said-Rahab's dialogue is full of interest, as showing the universal panic and consternation of the Canaanites on the one hand (Jos 24:11; De 2:25), and her strong convictions on the other, founded on a knowledge of the divine promise, and the stupendous miracles that had opened the way of the Israelites to the confines of the promised land. She was convinced of the supremacy of Jehovah, and her earnest stipulations for the preservation of her relatives amid the perils of the approaching invasion, attest the sincerity and strength of her faith.

2:8-21 Rahab had heard of the miracles the Lord wrought for Israel. She believed that his promises would certainly be fulfilled, and his threatenings take effect; and that there was no way of escape but by submitting to him, and joining with his people. The conduct of Rahab proved that she had the real principle of Divine faith. Observe the promises the spies made to her. The goodness of God is often expressed by his kindness and truth, Ps 117:2; in both these we must be followers of him. Those who will be conscientious in keeping promises, are cautious in making them. The spies make needful conditions. The scarlet cord, like the blood upon the doorpost at the passover, recalls to remembrance the sinner's security under the atoning blood of Christ; and that we are to flee thereto for refuge from the wrath of a justly offended God. The same cord Rahab used for the saving of these Israelites, was to be used for her own safety. What we serve and honour God with, we may expect he will bless, and make useful to us.