I see It refers to them all Sumadji. Outwardly it is applicable to the Messengers that were slain as part of their given Message, thus both Jesus and the Bab were the Lamb (in the history of Messengers there will be more). The Lamb as an Attribute of the Holy Spirit, is applicable to all the Messengers.
"....Man, the noblest and most perfect of all created things, excelleth them all in the intensity of this revelation, and is a fuller expression of its glory. And of all men, the most accomplished, the most distinguished and the most excellent are the Manifestations of the Sun of Truth. Nay, all else besides these Manifestations live by the operation of their Will, and move and have their being through the outpourings of their grace. “But for Thee, I would have not created the heavens.” Nay, all in their holy presence fade into utter nothingness, and are a thing forgotten. Human tongue can never befittingly sing their praise, and human speech can never unfold their mystery. These Tabernacles of holiness, these primal Mirrors which reflect the light of unfading glory, are but expressions of Him Who is the Invisible of the Invisibles. By the revelation of these gems of divine virtue all the names and attributes of God, such as knowledge and power, sovereignty and dominion, mercy and wisdom, glory, bounty and grace, are made manifest.
These attributes of God are not and have never been vouchsafed specially unto certain Prophets, and withheld from others. Nay, all the Prophets of God, His well-favored, His holy, and chosen Messengers, are, without exception, the bearers of His names, and the embodiments of His attributes. They only differ in the intensity of their revelation, and the comparative potency of their light. Even as He hath revealed: “Some of the Apostles We have caused to excel the others.”76 It hath therefore become manifest and evident that within the tabernacles of these Prophets and chosen Ones of God the light of His infinite names and exalted attributes hath been reflected, even though the light of some of these attributes may or may not be outwardly revealed from these luminous Temples to the eyes of men. That a certain attribute of God hath not been outwardly manifested by these Essences of Detachment doth in no wise imply that they Who are the Daysprings of God’s attributes and the Treasuries of His holy names did not actually possess it. Therefore, these illuminated Souls, these beauteous Countenances have, each and every one of them, been endowed with all the attributes of God, such as sovereignty, dominion, and the like, even though to outward seeming they be shorn of all earthly majesty. To every discerning eye this is evident and manifest; it requireth neither proof nor evidence.
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These attributes of God are not and have never been vouchsafed specially unto certain Prophets, and withheld from others. Nay, all the Prophets of God, His well-favored, His holy, and chosen Messengers, are, without exception, the bearers of His names, and the embodiments of His attributes. They only differ in the intensity of their revelation, and the comparative potency of their light. Even as He hath revealed: “Some of the Apostles We have caused to excel the others.”76 It hath therefore become manifest and evident that within the tabernacles of these Prophets and chosen Ones of God the light of His infinite names and exalted attributes hath been reflected, even though the light of some of these attributes may or may not be outwardly revealed from these luminous Temples to the eyes of men. That a certain attribute of God hath not been outwardly manifested by these Essences of Detachment doth in no wise imply that they Who are the Daysprings of God’s attributes and the Treasuries of His holy names did not actually possess it. Therefore, these illuminated Souls, these beauteous Countenances have, each and every one of them, been endowed with all the attributes of God, such as sovereignty, dominion, and the like, even though to outward seeming they be shorn of all earthly majesty. To every discerning eye this is evident and manifest; it requireth neither proof nor evidence.
The Kitáb-i-Íqán | Bahá’í Reference Library
A treatise revealed by Bahá’u’lláh in Baghdad in 1861/62 in response to questions posed by one of the maternal uncles of the Báb, translated by Shoghi Effendi and first published in English in 1931.
One can also consider that giving ones life is just one form of sacrifice. Baha'u'llah faced over 40 years of sacrificing His life for humanity, a bounty His Family shared. Muhammad was also long suffering as was Abraham and Moses. (All other Messengers also gave thier lives to give the Message God had Annointed them with.)
There is so much to consider on this topic. There are numerous ways to answer your question, that can be given.
Regards Tony
