Was the marriage of the Prophet, peace and blessings be upon him, to Juwayriyah bint Al-Harith due to her beauty, and does this contradict his great character mentioned in the verse: "And indeed, you are of a great moral character," knowing that this marriage led to the release of her tribe's captives and their conversion to Islam?

The Prophet, peace and blessings be upon him, married Juwayriyah bint al-Harith after her manumission contract was abrogated. The hadith (definition) does not state that the reason for his marriage to her was her beauty. Nevertheless, there is no harm in a man being attracted to a woman's beauty. The Prophet, peace and blessings be upon him, loved beauty, and this does not contradict the perfection of his character. His marriage to her was a goodness and blessing for her and for her people.