إِنَّ فِي ذَٰلِكَ لَآيَةً ۖ وَمَا كَانَ أَكْثَرُهُم مُّؤْمِنِينَ (67)
(26:67) There is indeed a Sign in this, *49 but most of these people would not believe.
*49) That is, the Quraish have this lesson to learn from this: "The obdurate people like Pharaoh, his chiefs and followers had not believed even though they had been shown clear miracles for years. They had been so blinded by obduracy that even on the occasion of their drowning in the sea although they had seen the sea parting asunder in front of their very eyes, the waters standing like high mountains on either side, and the dry path in between for the Israelite caravans to pass, yet they failed to understand that Moses had Divine succour and support with him which they had come out to fight. At last when they came to their senses, it was too late, because they had been overtaken by the wrath of Allah and the sea waters had covered them completely. It was on this occasion that Pharaoh had cried out "I have believed that there is no god but the real God in Whom the Children of Israel have believed and I am of those who surrender." (Yunus: 90).
On the other hand, there is a Sign in this for the believers, too. They should understand how Allah by His grace causes the Truth to prevail in the long run and the falsehood to vanish even though the forces to evil may appear to be dominant for the time being .