How can we reconcile the statement in Surat Maryam (Maryam Chapter), "Not one of you but will pass over it [Hell]," with the fact that martyrdom in the cause of Allah expiates sins and grants entry into Paradise?

There is no contradiction between the verses of the Holy Quran, specifically between the verses of "Al Imran" and "Maryam," for the words of Allah are free from imperfection.

The verse of "Al Imran" does not contradict the verse of "Maryam," and "entering Hellfire" is a certainty for all creations, even Muslims. Scholars have differed on the meaning of "entering" (al-wurud) mentioned in the verse of Maryam, with two main opinions: 1. Entering meaning direct entry: Where everyone enters Hellfire, then Allah saves the pious from it, while the oppressors and disbelievers remain therein. This is the opinion of Ibn Abbas. 2. Entering meaning passing over it: This is by passing over the Sirat (bridge) erected over Hell, and this is specific to the monotheists among Muslims. As for the disbelievers, they enter Hellfire directly. This is the opinion of Ibn Mas'ud.

Both meanings of wurud (entering/approaching) are found in the Book of Allah: wurud meaning direct entry (for disbelievers and those who commit sins), and wurud meaning drawing near or passing without entering (as in His saying, "When he came to the water of Midian").

The more probable opinion is that the wurud of Hellfire for monotheists is by passing over the Sirat, while for disbelievers it means direct entry, and this does not contradict the textual evidence.