Sayyiduna Abdullah ibn Abbas (may Allah be pleased with them both) explained this verse {وَاِذْ یَمْکُرُ بِکَ الَّذِیْنَ کَفَرُوْا لِیُثْبِتُوْکَ} by saying: The Quraysh consulted among themselves one night in Makkah regarding you (the Prophet Muhammad, peace and blessings be upon him). Some said: When morning comes, shackle him (Muhammad, peace and blessings be upon him) in chains. Some said: No, rather kill him. Some said: Rather, expel him. Meanwhile, Allah Almighty informed His Prophet of these matters. So Sayyiduna Ali (may Allah be pleased with him) spent that night on the bed of the Noble Prophet (peace and blessings be upon him), and the Noble Prophet (peace and blessings be upon him) left from there and took refuge in the Cave of Thawr. The polytheists spent the night guarding Sayyiduna Ali (may Allah be pleased with him), thinking they were guarding the Prophet (peace and blessings be upon him). When morning came, they rushed in, but they saw that it was Ali. In this way, Allah Almighty thwarted their plot. They said: Ali! Where is your companion? He said: I do not know. So they set out searching for the footprints of the Prophet (peace and blessings be upon him). When they reached that mountain, the matter became unclear to them. So they climbed the mountain and passed by the Cave of Thawr, but when they saw a spider’s web at its entrance, they said: If he (Muhammad, peace and blessings be upon him) had entered this cave, this spider’s web would not be here. Then the Prophet (peace and blessings be upon him) remained in that cave for three days.