Baha’is believe that there is an everlasting covenant which remains in force today. It will never be replaced.
The overall covenant God made with His followers in Judaism, known to Jews as the Mosaic Covenant, and to Christians as the Old Covenant, put forth the stipulation of the oneness of God – “Thou shalt have no other gods before me” (Exodus 20:2) – as the primary law of the Ten Commandments. In exchange for following those principles, God promised that he would never leave His followers without guidance:
Be strong and of a good courage, fear not, nor be afraid … for the Lord thy God, he it is that doth go with thee; he will not fail thee, nor forsake thee. – Deuteronomy 31:6.
This eternal covenant between God and humanity, the
Baha’i teachings say, remains in force today. The Creator has bestowed bounties on us all, and in return asks us to recognize His prophets and messengers and abide by their laws and spiritual principles. The Baha’i teachings joyously celebrate that covenant:
How to Understand the Baha’i Covenant
The everlasting covenant is like the umbrella which covers all religions. It began with Moses and it will last forever.
In addition to that covenant, the Messengers of God make a Covenant with their followers. This is called the Greater Covenant.
Jesus made a Covenant with His followers, which applies only to Christians.
Baha'u'llah also made a Covenant with His followers, which applies only to Baha'is.
Greater covenant
The greater covenant refers to the covenant made between each messenger from God, which the literature of the Baháʼí Faith name
Manifestations of God, and his followers regarding the coming of the next Manifestation from God.
[1] According to
Baháʼu'lláh, the founder of the Baháʼí Faith, God has promised that he will send a succession of messengers that will instruct humankind.
[2] In Baháʼí belief, this covenant is seen to be expressed in
prophecy in the
religious scripture of each religion, and each Manifestation of God, such as
Abraham,
Moses,
Jesus,
Muhammad, the
Báb,
[3] and Baháʼu'lláh, prophesied the next Manifestation.
[1] In return, the followers of each religion are seen to have a duty to investigate the claims of the following Manifestations.
[1]
https://en.wikipedia.org/wiki/Covenant of Baháʼu'lláh
The Lesser Covenant refers to succession of authority within each religion.
Lesser Covenant
This is the covenant that is made regarding the successorship of authority within the religion.
[1] In Baháʼí belief the manner in which the Covenant of Baháʼu'lláh was clearly put forth is seen as being a fundamental defining feature of the religion and a powerful protector of the unity of the Baháʼí Faith and its adherents.
[1]
https://en.wikipedia.org/wiki/Covenant of Baháʼu'lláh
Baha'is believe that the keys to the Kingdom were handed over to Peter. Jesus says this to Peter:
“I will give you the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven” (16:19). Baha'is believe that means that Jesus made a verbal Covenant with Peter and thus we uphold and defend the primacy of Peter as the Prince of the Apostles.
However, that authority was not upheld within the Church because there was no written Covenant as there is in the Baha'i Faith, and that is why Christianity split into hundreds of sects. That will never happen to the Baha'i Faith because Baha'is are faithful to the Covenant if Baha'u'llah, and if anyone tries to break away and start another religion and call it the Baha'i Faith the are removed from membership by the Universal House of Justice and deemed Convent-breakers.