In the first century Hijrah the paper industry was monopolized by the Romans and when the Christians of Egypt learned from the Romans how to manufacture paper and they produced it they following suit of the Romans, marked it (currency notes) with father-son and Rooh-ul-Qudus (Holy Spirit) which was the slogan of the Christians.
When "Abdul Malik Marwan", who was an intelligent and clever man, saw the mark of the paper and its meanings, he was very annoyed as to why Egypt, which was a Muslim country, used this mark. He at once wrote to his functionary and delegates in Egypt "From now onwards you must write upon them the slogan of monotheism."
The new papers with the monotheism mark upon it was circulated and reached the cities of Rome. Caesar the King of Rome got informed about it. He wrote still other letters to Abdul Malik warning and threatening him that if he did not evade that mark he would issue orders to produce coins with abusive language about the Prophet of Islam (P.B.U.H.) When those coins would be ready there would be no honor and dignity left over for him (Abdul Malik).
Abdul Malik thought if this thing happened I would be the dirtiest of all the Muslim rulers who caused such a thing to happen."
He immediately called a meeting and consulted with the officials and dignitaries of his country for many long hours, but to no result.
One of those present said, "The way out of this difficulty and its solution is this that we ask the answer to this problem and riddle from Imam Mohammad Baqir (A.S.)."
Abdul Malik liked his suggestion and at once ordered his governor in Madina to send Imam (A.S.) honorably and respectfully to Syria, and he himself detained the delegate of Caesar in Syria till such time Imam (A.S.) reached Syria to solve that problem.
When Imam reached Syria they reported the matter to him so that a way is sorted out for its solution. Imam (A.S.) said, "Caesar has frightened you he will actually not do it. God will not allow him to do this work. But the solution of it is this that you get the industrialist gathered and orders them to produce a coin with the chapter (Quranic chapter of Tawhid on one face and name of the Prophet [P.B.U.H.] on the other). In this way we will not need the Roman Coins any longer. Then he gave the explanation about the weight and size of the coin. Then he said, "Engrave the name of the city where the coin is made and the year of its production upon it."
Abdul Malik materialized the orders of the Imam (A.S.) and sent a circular to all the Islamic cities that from, now onwards all the business affair in the Islamic cities should take shape on the basis of the new coins, and the Roman Coins are invalid. Whosoever possesses them may change them for new Islamic coins. Then he informed the delegate of Caesar about what had been done and sent him back.
Caesar was informed about the affair. The courtiers demanded from him to materialize his threat. Hut he replied, "This is a futile thing to do. Because, the roman coins are no more used in the Islamic cities."
Imam by this amazing action put a constraint and checks upon the influence of imperialism and the plans of the imperialists of that day.
source : www.tebyan.net