“Every person sets out in the morning, trading with his own soul: he either emancipates it or ruins it.” (Narrated by Muslim)

[Explanation]
We have already discussed the verses that the author—may Allah have mercy on him—quoted regarding patience, its reward, the exhortation to it, and its proper place. He then, may Allah have mercy on him, began to cite the hadiths relevant to the subject.

He first mentioned the narration of Abu Mālik al-Ashʿarī (may Allah be pleased with him) in which the Prophet (blessings and peace be upon him) said, “Purification is one half of faith…” up to the words, “and patience is illumination.” In this hadith the Prophet (blessings and peace be upon him) explains that patience is an illumination—that is, it gives light to a person when darkness closes in and ordeals become severe. If he perseveres, that very patience becomes a lamp guiding him to the truth.

For this reason Allah—glorified is He—has listed patience among the means by which help is sought. It is a light within the believer’s heart and a light upon his path, his method, and his knowledge; for every step he takes toward Allah along the road of patience, Allah Most High increases him in guidance and the light within his heart, granting him clear insight. Hence the Prophet (blessings and peace be upon him) said, “Patience is illumination.”

As for the rest of the hadith, he (blessings and peace be upon him) said, “Purification is one half of faith.”

Purification here refers to a person’s cleanliness—both outward and inward—and “one half of faith” means that it constitutes half of faith.