The law of Moses abrogated the law of Abraham, and he is he [the same person]. The one who changed and substituted the law of Moses and untied his knot was Jesus, and he is he. The one who changed and substituted the laws of Jesus and Moses and untied their knots was Muhammad, and he is Moses, Jesus, and Abraham. As for the law of Muhammad, no one is permitted to untie its knot and change his Law [Sharia]. The knot of Muhammad ibn Abd-Allah is not untied except by Muhammad ibn al-Hasan the Proof [Al-Hujja]. The knot which al-Sadiq—peace be from him—spoke of is that which the Messenger of Allah (PBUH) tied on the Day of Ghadir regarding the guardianship [Walaya] of the Ain [Ali].

Another answer: The knot was established by Abu Shuaib [Muhammad ibn Nusayr], and likewise strengthened and magnified by al-Husayn ibn Hamdan [Al-Khasibi]. Whoever turns away from the path of al-Husayn is among those who have untied the knot.

He—may Allah sanctify him—excelled and bestowed favor with this meaning in another question from the book (Al-Ta'yid), which is a question about the fulfillment of contracts and exiting from the state of Ihram, and the witness from His (the Exalted) saying: {O you who have believed, fulfill the contracts. Lawful for you is the beast of grazing livestock} (Al-Ma'idah 1).