In the beginning of Islam, Rasulullah (sallallahu ‘alaihi wasallam) would not invite people openly to Islam, as he feared the harm and persecution of the kuffaar. He would invite in secret those people in whom he anticipated that they would accept his invitation and embrace Islam.
At that time, the few Muslims who were with Rasulullah (sallallahu ‘alaihi wasallam) would go to the mountains to perform salaah in secret, where they would not be seen or noticed by the kuffaar. When Rasulullah (sallallahu ‘alaihi wasallam) and the Sahaabah (radhiyallahu ‘anhum) wished to congregate, then they would do so in the home of Hazrat Arqam (radhiyallahu ‘anhu) which was situated on Mt Safaa.
This continued for three years, until the number of the Sahaabah (radhiyallahu ‘anhum) reached forty with Hazrat Umar (radhiyallahu ‘anhu) embracing Islam. After Hazrat Umar (radhiyallahu ‘anhu) embraced Islam, the Sahaabah (radhiyallahu ‘anhum) would gather wherever they wished. (Sharhuz Zurqaani 1/460, Isaabah 1/197 & Bidaayah wan Nihaayah 3/36)
After three years, Allah Ta‘ala revealed the following aayaat and commanded Rasulullah (sallallahu ‘alaihi wasallam) to openly proclaim the message of Islam and publicly invite the people towards Islam:
فَاصۡدَعۡ بِمَا تُؤۡمَرُ وَ اَعۡرِضۡ عَنِ الۡمُشۡرِکِیۡنَ ﴿۹۴﴾
Then proclaim openly that which you have been instructed (i.e. Islam) and turn away from the disbelievers. (Surah Hijr v. 94)
وَ اَنۡذِرۡ عَشِیۡرَتَکَ الۡاَقۡرَبِیۡنَ ﴿۲۱۴﴾ۙ
And warn your close relatives (of the fire of Jahannum which awaits the disbelievers) … (Surah Shu’araa v. 214)
وَ قُلۡ اِنِّیۡۤ اَنَا النَّذِیۡرُ الۡمُبِیۡنُ ﴿ۚ۸۹﴾
And say, “Indeed, I am the clear warner (of the punishment which awaits you if you do not bring imaan).” (Surah Hijr v. 89)
After these aayaat were revealed, Rasulullah (sallallahu ‘alaihi wasallam) ascended the mountain of Safaa and called out to the people of Makkah Mukarramah:
يَا صَبَاحَاهْ
Attention O people!
Among the Arabs, this announcement generally would be called out at the time of an emergency to gather the people and alert them of some great danger or the eminent attack of an enemy.
On hearing the call, the people of Makkah asked one another, “Who is calling out?” They were then told that it was none other than Muhammed (sallallahu ‘alaihi wasallam) who was calling out, and they all answered his call. Those who were able to come in person did so, while those who could not personally come sent someone in their place to hear the message on their behalf.
Rasulullah (sallallahu ‘alaihi wasallam) called out to the various clans of Makkah by name saying, “O Banu Abdil Muttalib! O Bani Fihr! O Bani Ka’b!”
Once they had all congregated, Rasulullah (sallallahu ‘alaihi wasallam) addressed them and said, “Tell me, if I inform you that there is an army of enemy horsemen at the foot of this mountain who wish to attack you, will you believe me?”
The people responded, “Yes, we will believe you, as we have never found you to be a liar!” Rasulullah (sallallahu ‘alaihi wasallam) then said “In that case, I am warning you of a severe punishment (that will befall you if you do not accept my message from Allah Ta‘ala).”
When Abu Lahab realised that Rasulullah (sallallahu ‘alaihi wasallam) had gathered the people to invite them to Islam, he became enraged and said:
تبا لك أما جمعتنا إلا لهذا
May you perish! Is this the only purpose for which you have gathered us here?
It was on this occasion that Surah Lahab was revealed in which Allah Ta‘ala cursed Abu Lahab and explained the severe punishment that awaits him and his wife in the fire of Jahannum. (Saheeh Muslim #208, Bidaayah wan Nihaayah 3/37)
In the narration of Saheeh Muslim, it is reported that when the various clans of the Quraish had answered the call of Rasulullah (sallallahu ‘alaihi wasallam) and gathered at Mt Safaa, he addressed each of the tribes individually by name saying, “O Banu La’b bin Lu’ayy! Save yourselves from the fire (of Jahannum by accepting Islam)! O Banu Murrah bin Ka’b! Save yourselves from the fire! O Banu Abdi Shams! Save yourselves from the fire! O Banu Abdi Manaaf! Save yourselves from the fire! O Banu Haashim! Save yourselves from the fire! O Banu Abdil Muttalib! Save yourselves from the fire! O Faatimah! Save yourself from the fire! I cannot benefit you before Allah Ta‘ala in any way (if you do not accept my way), however due to all of you being part of my family tribe, I will continue to water this relationship with its water (i.e. I will continue to maintain family relations with you, as this will be fulfilling your haq of kinship with me and a means for you embracing Islam)!” (Saheeh Muslim #204)
In some narrations, it is reported that Rasulullah (sallallahu ‘alaihi wasallam) had addressed certain family members by name, and invited them to Islam. Rasulullah (sallallahu ‘alaihi wasallam) said, “O Abbaas bin Abdil Muttalib! I cannot benefit you before Allah Ta‘ala in any way (if you do not accept my deen)! O Safiyyah, aunt of the Rasul of Allah, I cannot benefit you before Allah Ta‘ala in any way!” O Faatimah, the daughter of Muhammed, in this world, you may ask me for whatever you wish from my wealth (and I can give it to you, however, if you do not accept my way, then) I cannot benefit you before Allah Ta‘ala in any way.” (Saheeh Bukhaari #2753)