Is conjugal intercourse or intimacy considered fornication, and is it permissible to bathe with one's wife?

Intercourse or intimacy with one's wife is not adultery; rather, it is a great act of worship for which a Muslim is rewarded. The Prophet, peace and blessings be upon him, said: "And in the private part of one of you is charity." The "private part" (al-bada') here refers to the private parts. Adultery, on the other hand, is a man's intercourse with a woman who is not his wife, and it is among the greatest sins, as Allah Almighty says: "And do not approach unlawful sexual intercourse. Indeed, it is ever an immorality and a worst way." The difference between the two is immense. Intercourse with one's wife leads to lowering the gaze, protecting one's chastity, and increasing the Muslim nation. Adultery, however, leads to great evils and corruption in this world and the Hereafter, the ruin of families, and the mixing of lineages. Allah has associated adultery with shirk (polytheism) and murder in His saying: "And those who do not invoke with Allah another deity or kill the soul which Allah has forbidden [to be killed], except by [legal] right, and do not commit unlawful sexual intercourse." As for bathing with one's wife, it is permissible in Islamic law. It was narrated from Aisha, may Allah be pleased with her, that she used to bathe with the Prophet, peace and blessings be upon him, from a single vessel.