Nearby ayahs help place verse 29:68 in sequence and meaning.
لِيَكْفُرُوا۟ بِمَآ ءَاتَيْنَـٰهُمْ وَلِيَتَمَتَّعُوا۟ ۖ فَسَوْفَ يَعْلَمُونَ
So that they will deny what We have granted them, and they will enjoy themselves. But they are going to know.
أَوَلَمْ يَرَوْا۟ أَنَّا جَعَلْنَا حَرَمًا ءَامِنًا وَيُتَخَطَّفُ ٱلنَّاسُ مِنْ حَوْلِهِمْ ۚ أَفَبِٱلْبَـٰطِلِ يُؤْمِنُونَ وَبِنِعْمَةِ ٱللَّهِ يَكْفُرُونَ
Have they not seen that We made [Makkah] a safe sanctuary, while people are being taken away all around them? Then in falsehood do they believe, and in the favor of Allah they disbelieve?
وَٱلَّذِينَ جَـٰهَدُوا۟ فِينَا لَنَهْدِيَنَّهُمْ سُبُلَنَا ۚ وَإِنَّ ٱللَّهَ لَمَعَ ٱلْمُحْسِنِينَ
And those who strive for Us - We will surely guide them to Our ways. And indeed, Allah is with the doers of good.