Guidelines on speaking to a woman who is new in Islam for the purpose of da’wah
Question

A lot of people are justifying to one of our new Muslim sisters who just accepted Islam that she can talk to men, especialy muslim men as long as the niya is ok and they talk about Islam,I have read the answers to a few of similer topics but if their can be some clearer textual proofs from this question scince this sister does not have the proper proofs from any Hadeeth to go against the justifications they use,,can you bring clear evidances from the sunnah and the saluf-us saleh to once and for all close this subject to the sisters and brothers who say other wize and if thier are any acceptions in this matter? ,especialy in this case scince the new sister does not have that much knowledge and can easily be swayd from her lak of knowledge.
Praise be to Allah.May Allaah reward you with good for your gheerah (protective jealousy) with regard to the rulings of sharee’ah, especially with regard to those who enter Islam seeking refuge in it from the hell of deviant or distorted religions. With regard to what you have asked about, the issue of women who are new in Islam speaking to men, the texts of Islam have set out basic guidelines governing the relationship between men and women in a manner that achieves the aims of sharee’ah whilst also protecting Muslim men and women from the things that lead to fitnah. Wise people – even the kuffaar themselves – have attested to the effect that these general guidelines have had in reforming society; this is also to be seen from the history of Islam. 
Islam describes the basis of the relationship between the sexes in the Qur’aan and Sunnah. One of the most important texts is the verse (interpretation of the meaning):  
“O wives of the Prophet! You are not like any other women. If you keep your duty (to Allaah), then be not soft in speech, lest he in whose heart is a disease (of hypocrisy, or evil desire for adultery) should be moved with desire, but speak in an honourable manner”
[al-Ahzaab 33:32]
What is not allowed here is being soft in speech. So the woman should speak in an honourable manner. What this means, as the mufassireen have said, is that a woman should not make her speech soft when she speaks to men. Although this verse is addressed to the wives of the Prophet (peace and blessings of Allaah be upon him), the reason, which is to prevent evil and immoral men from entertaining indecent notions concerning the chaste Muslim women, is a reason that is general in meaning, so all the believing women are included here. Al-Jassaas said concerning this verse: It indicates that this is a ruling which applies to all women: they are forbidden to speak softly to men in a manner that might make them entertain indecent notions concerning them. Ahkaam al-Qur’aan, 5/229. 
Islam has sent out general guidelines in the light of which the details of specific issues may be worked out. We do not need to quote the evidence in detail for each matter. The general principle set out in this verse may cover many of the specific issues, including the situation under discussion here. In the answers to questions no. 1497, 1121, and 6543 you will find a detailed description of the guidelines concerning conversations between men and women; there is no need to repeat them here. 
The basic principle with regard to teaching the rulings of Islam is that the man should be the teacher, because Allaah has given him leadership [?] to act as imam and to issue fatwas and pass judgements, etc. Hence there is nothing wrong with women asking men about the rulings of Islam, as the women used to ask the Messenger of Allaah (peace and blessings of Allaah be upon him) about religious matters, especially if the woman who is asking is new in Islam and needs to learn rulings that will make sure her ‘aqeedah (belief) is correct and will increase her conviction and belief in this religion. When a man teaches a woman, that must be done in accordance with the Islamic guidelines referred to. 
It should be noted by our brothers who are conveying the message of Islam to that country – especially the young men among them – that the one who knows himself to be weak and fears that he may fall into the traps of the Shaytaan, namely becoming attracted to the women and being distracted from da’wah, should avoid being in direct contact with women when making da’wah, so long as there are others who are more able to do this task. If there is a need to speak to them, then he should do as little as possible. As for one who thinks that he can be steadfast and is sure of himself, the basic principle is that it is permissible for him to speak to women, but that is subject to conditions, as follows: 
1.Avoiding talking a great deal about matters other than the topic under discussion, or other than calling people to Islam.
2.Not joking or making the voice soft, etc.
3.Not asking about personal matters which have nothing to do with the topic, such as asking the woman’s age etc.
4.If some female daa’iyahs or women who are already Muslim can answer the questions, or if they can be answered through other media such as audiotapes or computer programs, that is better. It is also better if a number of trustworthy people can take on the task of teaching this new Muslim lady as this will make it less likely that a relationship or attachment will develop and she will become more attached to the religion than to the particular person who guided her to the religion.
5.Stopping talking to her immediately if there are any stirrings of attachment or desire in the heart; remembering that Allaah is always watching, because this is a hidden matter which is known to no one except the daa’iyah himself.
With regard to the new Muslim sister, he should explain to her the general evidence that sets out the guidelines for this relationship and the great wisdom behind it. The daa’iyah should be keen to guide her to focus her attachment on Allaah because that will be more effective in making her steadfast and keeping her away from forming an attachment to the men who have called her to Islam. If she does anything that is forbidden in sharee’ah in this regard, such as making her voice soft and so on, he should speak kindly to her so that Islam will become firmly rooted in her heart and she will develop a love for Islam. 
We ask Allaah to help us to convey the light and message of Islam and to follow His laws and the Sunnah of our Prophet Muhammad (peace and blessings of Allaah be upon him) in all our affairs.