Ibn Sarjadu, a rich merchant of Bagdad, had not gone through a regular course of academic instruction. He was chosen on account of his riches, as well as for his knowledge and energy. He occupied his position for eighteen years (943–960). He possessed a good philosophical education, wrote a philosophical work, and a commentary to the Pentateuch. Like Kohen-Zedek, Ibn Sarjadu endeavored to exalt the school of Pumbeditha at the expense of that of Sora. Questions were addressed to him from foreign countries. The school of Sora consequently, neglected and impoverished, received none of the revenue, and therefore could not train new pupils, who turned to richer Pumbeditha. This decline and decay of the school induced its chief, Joseph ben Satia, to abandon it, and to emigrate to Bassora (about 948). The school that had been founded by Rab was now closed, after it had continued in existence for seven hundred years. The people of Sora felt this so much that they made an energetic attempt to restore it. Four young men were sent abroad to awaken interest in the school, and to get contributions for it. But they did not attain their object. It seemed that fate was against them. They were captured at Bari, on the coast of Italy, by a Moorish-Spanish admiral, Ibn-Rumahis. They were transported, one to Egypt, another to Africa, a third to Cordova, and the fourth to Narbonne. Instead of assisting to raise the school of Sora, these four Talmudists unwittingly contributed to the downfall of the Gaonate.
The copies of the Talmud in Sora, which were now no longer used, were, later on, transferred to Spain. Babylonia, so long the center of Judaism, had to yield its supremacy in favor of a foreign place. The decay of one of the Babylonian schools, and the decline of interest that followed upon it, were utilized by the Karaites to make converts amongst the Rabbanites. They did this with such zeal that they thought they were about to strike the death-blow to Rabbanism. As long as Saadiah, the mighty champion of Rabbanism, lived, they did not venture to do anything to expose themselves to his criticism. But after his death, when they perceived that there was no man of any importance to stand in the breach, they hoped to obtain an easy victory. Saadiah's opponent, Solomon ben Yerucham, immediately hastened from Palestine to Babylonia, in order to prove to the followers of Saadiah, that he had misrepresented facts in his defense of the Talmudists. Thus he expected to bring over the Rabbanites to Karaism.
But a more vehement, zealous and cunning proselytizer was Abulsari Sahal ben Mazliach Kohen, an inhabitant of Jerusalem, who belonged to the ascetic section of the Karaite community. Abulsari Sahal had a thorough knowledge of Arabic and Hebrew, and wrote in a much more elegant style than any of his contemporaries. He compiled a Hebrew grammar, commentaries to several books of the Bible, and also a compendium of religious duties under the title "Mizvoth." However, he did not write anything of great consequence. The Karaites seem to have had no ability to get beyond beginnings; certainly not Sahal, who was possessed by sombre, monkish piety. To his co-religionists, nevertheless, he appeared in the light of a great teacher. Sahal also wrote a refutation of Saadiah's attacks upon Karaism. It was, doubtless, considered an honorable thing amongst the Karaites, to win one's spurs in combat with this great champion. Sahal appears to have delivered his lectures against the Rabbanites in Bagdad. He called upon the people to renounce tradition, and to refuse obedience to the schools, "which were the two women of whom the prophet Zechariah speaks, and who carried sin and left it in Babylon." Sahal implored his hearers to renounce the indulgences that their Rabbanite teachers allowed them, such as keeping oil in camel-skins, purchasing bread from Christians and Mahometans, and leaving their houses on a Sabbath.
Sahal's attacks upon the Rabbanites were too offensive to remain unanswered. An influential Rabbanite seems to have forced him into silence by aid of the government. Saadiah's pupil, Jacob ben Samuel, stung to the quick by the abuse which Sahal and other Karaites had heaped upon his master, took up the cudgels in his behalf. He delivered speeches in the streets and in the public places against Karaism and the proselytizer Sahal. The latter, however, did not remain silent. In a passionate letter to Jacob, written in beautiful Hebrew, he continued his attacks, and gave a faithful picture of the state of Karaism and Rabbanism in his time, leaving out neither the light nor the shade of both sides. After the versified attack and the reproaches for Jacob's incorrect Hebrew and the injury done to Judaism by the Rabbanites, Sahal proceeds:
I am come from Jerusalem in order to warn the people, and to bring them back to the fear of God. Would that I had the power of going from town to town to awaken the people of the Lord. You think that I came here for the sake of gain, as others come who grind the faces of the poor; but I came in the name of God, in order to bring back the thoughts of the people to true piety, and to warn them not to rely on human institutions, nor to listen to the sayings of the two evil women (the Gaonic schools). How shall I not do it, since my heart is moved by the irreligion of my brethren, who are walking in the wrong path, who impose a heavy yoke upon the ignorant people, who oppress them and rule over them through excommunication and persecution, who call to their aid the power of the Mahometan officials, who compel the poor to borrow money on interest, in order to benefit by it and to be able to bribe the officials? They feed themselves, but not their flocks, and they do not teach the word of God in the proper way. If any one asks them the reason for anything they do, they antagonize him. Far be it from me that I should be silent, when I see that the leaders of the community, who say that they constitute the Synhedrion, eat without compunction with non-Jews. How shall I be silent, when I perceive that many of my people make use of idolatrous practices? They sit on the graves of the departed and invoke the dead, and pray to Rabbi José the Galilean, saying, "O heal me, and make me fruitful." They make pilgrimages to the shrines of the pious dead, light candles there, and burn incense. They also make vows that they may be cured of their diseases. O that I had the power to go everywhere and to proclaim it aloud, to admonish men in the name of the Lord, and to deter them from their evil course. And now, O House of Israel, have mercy on your souls, and choose the right path. Do not object and say that the Karaites, too, differ among themselves as regards religious duties, and that you are in doubt with whom to find truth. Know, therefore, that the Karaites do not wish to exercise authority; they only desire to stimulate research. You ask, What should the ignorant do who is unable to search the Holy Scriptures? I tell you that such a one has to rely upon the results arrived at by the investigator and the expounder of Holy Writ.
At the end, Sahal prophesied that God would destroy the yoke of the two women, as it is written in the prophets: "Then and then only will the sons of Israel be reconciled and united, and the Messiah come."
Another prolific Karaite author from Bassorah, Jephet Ibn-Ali Halevi (950–990), wrote polemics against the same Jacob ben Samuel. Jephet was considered a great teacher by the Karaites. He was a grammarian, commentator and expounder of the Law, but he was not free from the errors of the members of his creed. His style was bombastic and diffuse, and like them, he was superficial and literal-minded. The want of Talmudic dialectics is severely missed in the Karaite authors, for it rendered them tedious talkers. Jephet's absurd polemic against Saadiah's pupil bears this stamp of superficiality and insipidity, and it never displays the beautiful Hebrew style of his contemporary and friend Sahal.
Solomon ben Yerucham, who continued to write till a very old age (certainly till 957), composed commentaries to the Pentateuch and the Hagiographa, and other works no longer known. He was a sworn enemy to philosophical research. In his commentary on the Psalms, he bitterly complains that Jews occupy themselves with heretical writings, whose authors and teachers he curses severely.
"Woe to him," he cries, "who leaves the Book of God and seeks others! Woe to him who passes his time with strange sciences, and who turns his back upon the pure truth of God! The wisdom of philosophy is vain and worthless, for we do not find two who agree upon a single point. They propound doctrines which directly contradict the Law. Amongst them there are some who study Arabic literature instead of always having the word of God in their mouths."
What a contrast there is between Saadiah and his Karaite opponent! The one studied philosophy, and took it into the service of Judaism; the other (without any knowledge of it) declared it heretical, and allowed his Judaism to become petrified. The Rabbanites entered into the temple of philosophy, and the Karaites shunned it as an infected house.