In chapter 55 of the Qur'an (Surah 55 "The Merciful") there is a passage about beautiful virgins in Paradise known as "huris":
"Which is it, of the favours of your Lord, that ye deny? Therein are those of modest gaze, whom neither man nor spirits will have touched before them. Which is it, of the favors of your Lord, that ye deny?"The number of these virgins is not provided in the Qur'an, but Islamic holy Traditions - Hadith - state that there will be 70 or 72 of them, or that every man will have 70 wives.
In the Book of Certitude, Baha'u'llah explains that the Holy Books are written in two modes: One is clear and unveiled, and the other is "veiled and concealed" and according to Islamic tradition has 70 concealed meanings:
"It is evident unto thee that the Birds of Heaven and Doves of Eternity speak a twofold language. One language, the outward language, is devoid of allusions, is unconcealed and unveiled; that it may be a guiding lamp and a beaconing light whereby wayfarers may attain the heights of holiness, and seekers may advance into the realm of eternal reunion. Such are the unveiled traditions and the evident verses already mentioned. The other language is veiled and concealed. . . None apprehendeth the meaning of these utterances except them whose hearts are assured, whose souls have found favour with God, and whose minds are detached from all else but Him. In such utterances, the literal meaning, as generally understood by the people, is not what hath been intended. Thus it is recorded: 'Every knowledge hath seventy meanings, of which one only is known amongst the people. And when the Qá'im shall arise, He shall reveal unto men all that which remaineth.'"So here Baha'u'llah quotes a Muslim Tradition stating that the Word of God has 70 meanings. Earlier in this same Book, Baha'u'llah linked His explanations of the inner meanings enfolded within the Word of God, with the huris mentioned in the Qur'an:
(Baha'u'llah, The Kitab-i-Iqan, p. 254; compare Luke 8:9-10)
"By God! however great Our desire to be brief, yet We feel We cannot restrain Our pen. Notwithstanding all that We have mentioned, how innumerable are the pearls which have remained unpierced in the shell of Our heart! How many the huris of inner meaning that are as yet concealed within the chambers of divine wisdom! None hath yet approached them; -- huris, 'whom no man nor spirit hath touched before.'"Therefore, it is my understanding that the 70 virgins in "Paradise" that are untouched by any man, are the 70 meanings in the Paradise of the Word of God not previously understood by any mind. Perhaps this is an example of Shoghi Effendi's statement that in the Book of Certitude Baha'u'llah unfolds the meaning of the "cryptic Muhammadan traditions" that have been misunderstood in the past.
(Baha'u'llah, The Kitab-i-Iqan, p. 70)