|| The message
The general message of all the messengers were that humans and their existence is part of larger events that spans billions of years. It started with God the almighty wanting to create a race that will worship Him without having seen Him. When we were born we came from Him and when we die we return to Him. This world and life is the test bed to separate the good souls form the evil.
|| Faith, trusting in God as one and only
Faith is the foundation of the messengers' teachings. Recognizing God as one and only, who doesn't have any partner. And all worship should be subjected to Him. That's acceptance.
|| The afterlife