If one girl & boy are fall in love & both of them say kobul by mobile phone. So what will happen ? In Islamic view are they will husband & Wife ?

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According to Shariah, the wife-to-be says, 'An Kah'tu nafsaka a'lal mah'ril ma'loom'. ("I have given away myself in Nikah to you, on the agreed Mahr.")

Immediately, the man (bridegroom) says, 'Qabiltun Nikaha'. ("I have accepted the Nikah.")

With these pronouncements, they become husband and wife.

If the marrying partners are not able to recite the formula in Arabic, one or two persons or priests are appointed and authorized to officiate. One who represents the bride would first seek her explicit consent to officiate on her behalf, and so would the other who acts on behalf of the groom. Naturally, there would be a slight variation in the pronouncements, because the persons reciting them are appointees. A person who represents the bride would initiate by saying, "Ankah'tu muwakkilati muwakkilaka a'lal mah'ril ma'loom." ("I give away in Nikah the woman who has thus appointed and authorized me, to the man who has authorized you, on an agreed Mahr.")

The groom's representative would respond, "Qabiltunnikaaha limuwakkili a'lal mah'ril ma'loom." ("I accept the Nikah on behalf of the one who has appointed me, on the agreed Mahr.")

It is mustahab to recite a brief discourse or Khutba before the Nikah formula is enunciated. In this Khutba, Allah is praised for His Wisdom in regulating the lawful process of procreation, and then the traditions from Holy Prophet Muhammad (s.a.w.) are also recited.