Tafsir of Maryam 19:20

"The touch" (al-mass) is used here as an expression for lawful marriage, as it is a metonymy for it. This is like the Almighty’s saying: "Before you have touched them" (Al-Baqarah: 237), or "Or you have had contact with women" (An-Nisa: 43).

Adultery is not referred to in this manner; rather, one says of it: "He committed lewdness with her," "He acted wickedly with her," and similar expressions. It is not fitting for the nuances of metonymy and etiquette to be observed in that context.

"A harlot" (baghiyy): The immoral woman who seeks men. According to al-Mubarrad, it is on the measure of fa‘ūl (derived from baghawiyy), where the waw was assimilated into the ya’. Ibn Jinni stated in Kitāb al-Tamām that it is on the measure of fa‘īl; for if it were fa‘ūl, it would have been said baghū, just as one says, "So-and-so is nahū (one who forbids) evil."

"And that We may make him a sign": The reason for which this was done is omitted. It means: "We did that so that We might make him a sign for the people." Alternatively, it is conjoined to an implied reason, meaning: "So that We may manifest Our power through him, and that We may make him a sign." Similar examples include: "And Allah created the heavens and the earth in truth, and that every soul may be recompensed for what it has earned" (Al-Jathiyah: 22), and His saying: "And thus We established Joseph in the land, and that We might teach him" (Yusuf: 21).

"A matter already decreed" (maqḍiyyan): Ordained and inscribed in the Preserved Tablet, which must inevitably come to pass for you. Or, it was a matter worthy of being and being decreed, because it is a sign and a mercy.

The "sign" (āyah) refers to the lesson and the proof of Allah’s power. The "mercy" (raḥmah) refers to the laws, divine favors, and whatever serves as a cause for strengthening belief and attaining obedience and righteous deeds; such a thing is worthy of being brought into existence.