What are the signs: Some signs of Laylat al-Qadr (the Night of Decree) have been mentioned in the authentic hadith, which help in identifying this night. Some of these signs are physical, while others are related to spiritual effects.
What are the signs, When Hazrat Ubayy ibn Ka’b (may Allah be pleased with him) was told that Hazrat Abdullah ibn Mas’ud (may Allah be pleased with him) said: “Whoever stays in prayer for a whole year, he has found Laylat al-Qadr.” Ubayy (may Allah be pleased with him) said: “By Allah, besides whom there is no god! That night is in Ramadan… He used to swear without any exception… And by Allah! I know very well which night that is, it is the same night in which the Messenger of Allah (peace and blessings of Allah be upon him) commanded us to stay in prayer. It is the night of the twenty-seventh dawn, and its sign is that the sun rises white on the morning of that day, without any rays.”
(Sahih Muslim: 762)
The weather on this night is mild and pleasant, neither too hot nor too cold. Thus, it is mentioned in a hadith:
Sayyiduna Jabir bin Abdullah (may Allah be pleased with him) reported that the Messenger of Allah (peace and blessings of Allah be upon him) said: “Indeed, I was shown the Night of Decree, then I was forgotten, and it is a night of the last ten days. It is a bright, calm night, neither hot nor cold.” Mr. Al-Zayyadi added: “It is as if the moon is dimming the light of its stars on this night.” Both narrators reported: “The devils do not come out on this night until the dawn breaks.”
(Sahih Ibn Khuzaymah: 2190)
Some scholars have mentioned that a person who worships on this night gains a special kind of spiritual joy and peace.