The Qur'an is a Reminder, and Guidance comes from the Help of Allah

Allah then says,

﴿ إِنَّ هَـٰذِهِۦ تَذۡكِرَةٌ۬‌ۖ ﴾

(Verily, this is an admonition,) meaning, this Surah is a reminder.

﴿ فَمَن شَآءَ ٱتَّخَذَ إِلَىٰ رَبِّهِۦ سَبِيلاً۬ ﴾

(so whosoever wills, let him take a path to his Lord.) meaning, a path and a way. This means, whoever wishes to be guided by the Qur'an. This is similar to Allah's statement,

﴿ وَمَاذَا عَلَيۡہِمۡ لَوۡ ءَامَنُواْ بِٱللَّهِ وَٱلۡيَوۡمِ ٱلۡأَخِرِ ﴾

(And what loss have they if they had believed in Allah and in the Last Day.) (4:39) Then Allah says,

﴿ وَمَا تَشَآءُونَ إِلَّآ أَن يَشَآءَ ٱللَّهُ‌ۚ ﴾

(But you cannot will, unless Allah wills.) meaning, no one is able to guide himself, enter into faith or bring about any benefit for himself,

﴿ إِلَّآ أَن يَشَآءَ ٱللَّهُ‌ۚ إِنَّ ٱللَّهَ كَانَ عَلِيمًا حَكِيمً۬ا ﴾

(Unless Allah wills. Verily, Allah is Ever All-Knowing, All-Wise.) meaning, He is Most Knowledgeable of who deserves to be guided. So, He makes guidance easy for him and He predestines for him that which will be a cause for it. However, whoever deserves misguidance, He averts guidance from him. Unto Him belongs the most excellent wisdom and the most irrefutable argument. Thus, He says,

﴿ إِنَّ ٱللَّهَ كَانَ عَلِيمًا حَكِيمً۬ا ﴾

(Verily, Allah is Ever All-Knowing, All-Wise.) Then He says,

﴿ يُدۡخِلُ مَن يَشَآءُ فِى رَحۡمَتِهِۦ‌ۚ وَٱلظَّـٰلِمِينَ أَعَدَّ لَهُمۡ عَذَابًا أَلِيمَۢا ﴾

(He will admit to His mercy whom He wills and as for the wrongdoers -- He has prepared a painful torment.) meaning, He guides whomever He wishes and He leads astray whomever He wishes. Whoever He guides, there is no one who can lead him astray; and whoever He leads astray, there is no one who can guide him. This is the end of the Tafsir of Surat Al-Insan. And all praise and thanks are due to Allah.