Arabic (Original)
وَبِإِسْنَادِهِ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ لَا تَقَدَّمُوا الشَّهْرَ بِيَوْمٍ وَلَا يَوْمَيْنِ إِلَّا أَنْ يُوَافِقَ أَحَدُكُمْ صَوْمًا كَانَ يَصُومُهُ صُومُوا لِرُؤْيَتِهِ وَأَفْطِرُوا لِرُؤْيَتِهِ فَإِنْ غُمَّ عَلَيْكُمْ فَأَتِمُّوا ثَلَاثِينَ يَوْمًا ثُمَّ أَفْطِرُوا.
English Translation
And with the same chain of narration, the Messenger of Allah (peace be upon him) said: "Do not precede the month (of Ramadan) by one or two days, unless it coincides with a fast that one of you regularly observes. Fast when you see it (the new moon) and break your fast when you see it. If it is obscured from you, complete thirty days, then break your fast."