Allah then says,

﴿إِنَّ هَـذِهِ تَذْكِرَةٌ﴾

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

﴿فَمَن شَآءَ اتَّخَذَ إِلَى رَبِّهِ سَبِيلاً﴾

(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 عَلَيْهِمْ لَوْ ءَامَنُواْ بِاللَّهِ وَالْيَوْمِ الاٌّخِرِ﴾

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

﴿وَمَا تَشَآءُونَ إِلاَّ أَن يَشَآءَ اللَّهُ﴾

(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,

﴿إِلاَّ أَن يَشَآءَ اللَّهُ إِنَّ اللَّهَ كَانَ عَلِيماً حَكِيماً﴾

(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 اللَّهَ كَانَ عَلِيماً حَكِيماً﴾

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

﴿يُدْخِلُ مَن يَشَآءُ فِى رَحْمَتِهِ وَالظَّـلِمِينَ أَعَدَّ لَهُمْ عَذَاباً أَلِيماً ﴾

(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.