Tafsir of Al-Qasas 28:51

"And We have connected for them..."

It is read: waṣṣalnā (with a shadda) and waṣalnā (without a shadda).

The meaning is: The Qur’an has come to them successively and continuously—containing promises and warnings, stories and lessons, exhortations and advice—with the intention that they might remember and thus succeed.

Alternatively, it means it was sent down to them in a continuous manner, one part following another, as in His saying: "And no fresh reminder comes to them from the Most Merciful except that they turn away from it" (al-Shuʿarāʾ: 5).

"Those to whom We gave the Book before it, they believe in it."