I heard Allah's Messenger (ﷺ) (p.b.u.h) saying, "We (Muslims) are the last (to come) but (will be) the
foremost on the Day of Resurrection though the former nations were given the Holy Scriptures before
us. And this was their day (Friday) the celebration of which was made compulsory for them but they
differed about it. So Allah gave us the guidance for it (Friday) and all the other people are behind us in
this respect: the Jews' (holy day is) tomorrow (i.e. Saturday) and the Christians' (is) the day after
tomorrow (i.e. Sunday)."
Sahih al-Bukhari Book 11, Hadith 1