How can my intention be pure when honestly my heart wants Paradise and fears the Fire? Isn’t that still working for a reward?

Set that worry down. Hope of the Garden and fear of the Fire do not stain your worship. Those two were placed in the hearts of Allah’s nearest servants, and He praised them for it.

Of His chosen ones, the prophets, He says:

“And they used to call upon Us in hope and fear.”

Qur’an, Al-Anbiya 21:90 · meaning

And of those whose sides forsake their beds at night to call upon their Lord:

“They call upon their Lord in fear and hope.”

Qur’an, As-Sajdah 32:16 · meaning

So this is not a lower path. Hope and fear are not wages you demand from Allah; they are the two hands with which you reach toward Him. A small child runs to a parent partly for the sweetness of the embrace and partly because of the dark room behind him, but either way he is running toward one face. He is not a mercenary. He is in love.

Look also at what hope and fear actually are underneath. Hope of Paradise is longing for His nearness and His pleasure. Fear of the Fire is dread of being turned away from His door. Both of them are about Him. As the heart matures, these two carry you higher, until you scarcely notice you are flying, so taken up will you be with the One you fly toward.

Those who study the heart in our own time have noticed one part of this: devotion carried mainly by fear and self-pressure tends to sit heavy on a person, while a heart that holds its Lord to be good carries the same worship more lightly. The pairing of hope with awe is no discovery of theirs, though. The Qur’an placed the two together long before.

One small step: Tonight, in a single supplication, ask Allah once for His Paradise and seek refuge once from His Fire, then add three words after them, “and I want only You.”