I have a little while before Shabbat starts, so I'll share some thoughts.
"You are My witnesses, says the LORD, and My servant whom I have chosen; that you may know and believe Me, and understand that I am He; before Me there was no God formed, neither shall any be after Me." (Isaiah 43:10)
When HaShem created the world, He intended for all of man to recognize and worship Him. After the failure of Adam and the generation of the Flood, HaShem realized that He needed a special nation that would belong directly to Him through which He could spread His truth. "When the Most High gave to the nations their inheritance, when He separated the children of men, He set the borders of the peoples according to the number of the children of Israel. For the portion of the LORD is His people, Jacob the lot of His inheritance." (Deut. 32:8-9). HaShem chose our Father Avraham so bring the message of monotheism and ethics to the world. Avraham was a revolutionary, smashed his father's idols and upset the social order. When brought before the wicked tyrant Nimrod, Avraham chose to have himself thrown into the fiery furnace rather than betray HaShem his G-d, setting a precedent which so many Jews would later follow rather than forsake the faith of their ancestors.
When Yaakov's family descended to Egypt to escape the famine, they eventually settled there and were enslaved by Pharaoh. True to His word, HaShem redeem the Children of Israel, removed the degraded rabble from the humiliation of slavery, and gave them the Torah at Mount Sinai, the very reason for their freedom. Throughout this Torah, HaShem gave His beloved children myriads of mitzvot to bear witness to their Creator and to His redemption. The Jews were to wear tzitzit, fringed tassels on the corners of our garments that "ye may look upon it, and remember all the commandments of the LORD, and do them; and that ye go not about after your own heart and your own eyes, after which ye use to go astray; that ye may remember and do all My commandments, and be holy unto your God." (Num.15:39-40) Upon every doorpost, Jews were to inscribe G-d's commandments and place mezuzot in memory of the blood that the Jews placed on their doorposts that G-d could pass over their homes in Egypt. As soon as the Jews left Egypt, they were commanded on several occasions to teach their children about the miracles that G-d performed for them their and to keep the holidays in commemoration of the events of their redemption. The Jew, upon waking up and going to bed, and before he leaves this world, was to proclaim proudly "Hear O Israel, HaShem is Our G-d, HaShem is One!" This was to be his testimony. The Jew was G-d's witness to His Oneness, to His Truth and to His Grandeur.
The entire Jewish people, from old to young, men and women, stood at Mount Sinai and heard G-d's voice declare “I am the Lord your God who brought you out of the land of Egypt, from the house of bondage. You shall not have any other gods beside Me.” This is how God demonstrated to His people who it is they are to worship. At the same time God was teaching the people whom they are not to worship. Worship of anyone other than the God who brought the nation out of Egypt, is idolatry. The Jewish scriptures testify that the Sinaitic revelation was an all-inclusive demonstration. After the revelation at Sinai there can be no room for doubt. Concerning this revelation Moses tells the Jewish people “To you it was demonstrated in order that you know that the Lord is the God, there is none beside Him.” It was engraved upon their hearts from that moment when HaShem bought their eternal allegiance that it was the duty of the Jewish people to worship only the G-d that brought us out of Egypt and no other. HaShem identified the idols quite clearly, by saying "that which I have not commanded" or "that which you do not know" (Deut. 13,18). Anything that HaShem did not specifically command to worship at Sinai is an idol.
The Jewish people were exiled across the world, just as the Torah predicted. Also in accorance to the Torah, many Jews left Judaism and they served gods of wood and stones which their fathers knew not (Deut. 28:64), converting en masse to Christianity, which worships a man nailed to wood, or to Islam, whose adherents bow to a black stone in Mecca. The majority of the Jewish people, however, remained faithful to the G-d that took them out of Egypt and continued bearing testimony to His name. Despite all of the attempts to wean them off of their Torah, the Jews knew that no god could claim the same allegiance as HaShem who saved them from the oppression of Egypt. This nation was never moved to reject the testiony of the ancestors, the ones who acted as G-d's Witnesses.
Jews, do not forget your calling, to bear witness to HaShem's Unity, to His Glory. Do not be discouraged at the tauntings of the nations that we are forsaken, that we are in error, that we are dejected. HaShem, who has been with us through the long exile, has never abandonned us. He will redeem us soon, again, like in the days of the Exodus from Egypt. The nations are in error and despite their claims, someday soon we will be vindicated. "In those days it will happen that ten men, of all [different] languages of the nations, will take hold, they will take hold of the corner of the garment of a Jewish man, saying, 'Let us go with you, for we have heard that God is with you!" (Zech. 8:23). Truth has never left the Jewish nation because we still practice the same ways as we did over 3500 years ago. It is not us who are wrong, but the nations who refuse to listen to G-d's Witnesses or to their tesimony.
"O LORD, my strength, and my fortress, and my refuge in the day of affliction, the Gentiles shall come unto thee from the ends of the earth, and shall say, Surely our fathers have inherited lies, vanity, and [things] wherein [there is] no profit. Shall a man make gods unto himself, and they [are] no gods?" (Jer. 16:19)