Gregory the Dialogist

And he had fourteen thousand sheep, and six thousand camels, and a thousand yoke of oxen, and a thousand she asses; and he had seven sons, and three daughters. 36. That he had had seven thousand sheep, and three thousand camels, five hundred yoke of oxen, and five hundred she asses, before the trial of his scourging, the preface of this same history points out to us. Those things which were lost through his scourging, were now restored twofold. But as many children were restored as he had lost. …

Morals on the Book of Job, Book XXXV ↗

Thomas Aquinas

Now Job had lost not only his possessions, but also his children who are restored to him, but not double what he had before, for the text says, "He had seven sons and three daughters." There can be two reasons for this. One pertains to the future life, because the sons which he had were not completely lost to him but were saved in the future life to live with him. …

Commentary on Job ↗