Imam As-San'ani said: "The narration is evidence to exaggerate the sniffing when not fasting. Exaggeration is forbidden when fasting in case something comes down the throat and ruins the fasting."

　　Another narration says: "Whoever does a deed, not in our religion, is rejected." In addition, the Quran and Sunnah stated that abstinence is when we can detect the white line from the black line at dawn. When they are detected, everyone has to stop eating and drinking. Allah Says (what means): "Eat and drink until you can distinguish between the black line and white line at dawn." [Quran; 2:187] The Prophet said: "Bilal calls for salah at night. Eat and drink until Ibn Um Maktoom calls." Ibn Um Maktoom was a blind man who did not call for prayer until he was told it is time. From the previous verse and narration, it is clear that abstinence should be at dawn and that the Athan is a sign of it. Therefore when the Athan starts, it is time for abstinence and not when he says "haya ala assalah."

　　Then complete the fast till the night [i.e. sunset]." [Quran; 2:187]

　　[Al-Bukhari and Muslim] Imam Ahmad Ibn Nasr Al-Marozy said after mentioning the above verse: "The scholars have agreed that if the sun has set, that means night has begun and it is time to break the fast."

　　[Al-Bukhari and Muslim]. He also narrated that the Prophet said: "My nation is still following my Sunnah as long as they don’t wait for the stars to break their fast." [Ibn Hibban] Abu Hurayrah narrated that he Prophet said: "Our religion will stay visible as long as people hasten breaking their fast because the Jews and Christians delay."

　　[Al-Bukhari and Muslim]. Ash-Shawkani referred to this when speaking about the dispute about whether the smell of a fasting person's breath was meant to be in this life on earth or in the hereafter. He said: "Due to this dispute, it was said that siwak is disliked when fasting." He then said: "In truth the siwak is desirable for a fasting person to use in the morning and in the late afternoon and that is the opinion of the majority of scholars." What also proves the permissibility of the Siwak is the fact that the Prophet generalized when he said: "If it wasn’t going to be tough on my nation, I would have ordered them to use the Siwaak at every prayer." Imam Al-Bukhari said: "The Prophet did not specify a fasting or non-fasting person."