First Pledge at Aqaba-
Twelve men from among the Aus and Khazraj of the Medina met Muhammad at al Aqaba and pledged allegiance to him, to protect him as they would their own women and children. They would in return accept him as their leader and to obey him. This was called the 'Pledge of Women' - meaning no fighting is involved - which was before Muhammad changed the rules and made the duty to make war mandatory(Ishaq198)
Second Pledge at Aqaba-
The meeting was held between the Ansar (Aus and Khazraj from the Medina who accepted Islam) of seventy three men and two women with Muhammad and his uncle
They agreed to protect him as they would their women and children and in return for obeying and being faithful to him they would be rewarded with a place in Paradise.
He chose twelve leaders from among them, nine from the Khazraj and three from the Aus (II 201). Tradition relates that Allah gave Muhammad permission to go to war and shed blood at this meeting
2: 193 And fight them on until there is no more tumult or oppression and there prevail justice and faith in Allah; but if they cease let there be no hostility except to those who practice oppression.
22: 39 To those against whom war is made permission is given (to fight) because they are wronged and verily Allah is Most powerful for their aid
*** Muhammad never failed to copy from the Biblical stories and emulate them in his own lifetime. The chosen twelve were in similitude to the leaders of the twelve tribes of Israel as well as the disciples of Jesus.
At this meeting there was a prophetic statement made by al Abbas b Utada b Nadla al Ansari who told all those who pledged allegiance to Muhammad-
" O, men of Khazraj, do you realize to what you are committing yourselves in pledging support to this man? It is to war against all and sundry!"
*** Approximately 1450 years ago, in the 7th century, Muhammad in his Quran declared WAR against ALL HUMANS who do NOT BELIEVE as he does.
This legacy continues with even greater tenacity in the 21st century ***
For accepting to protect Muhammad as they would their women and children, they asked Muhammad what they would be getting in return for their loyalty, he promised them Paradise. (Ishaq 204-5).
Hence, while the Aus and Khazraj put their lives and those of their families in mortal danger in the real world, Muhammad gave them his cheap promises of Paradise in the Afterlife.
Since no one has ever been resurrected to describe Paradise or Hell, this was a very one-sided contract where in, only Muhammad was the winner.
In the second pledge there were conditions involving war which were not in the first. ***