Our Lady tells you why she appears in Medjugorje

Message dated February 8, 1982
You ask me the sign to believe in my presence. The sign will come But you don't need it: you yourself must be a sign for others!
Some passages from the Bible that can help us understand this message.
Genesis 9,8-19
God said to Noah and his sons with him: As for me, behold, I make my covenant with your descendants after you; with every living being that is with you, birds, cattle and wild beasts, with all the animals that have come out of the ark. I establish my covenant with you: no living thing will be destroyed by the flood waters, nor will the flood devastate the earth any more. God said: This is the sign of the covenant, which I place between you and me and between every living being that is with you for eternal generations. My bow lay on the clouds and it will be the sign of the alliance between me and the earth. When I gather the clouds on earth and the arch appears on the clouds, I will remember my alliance that is between me and you and between every being who lives in all flesh and there will be no more waters for the flood, to destroy all flesh. The arch will be on the clouds and I will look at it to remember the eternal covenant between God and every being who lives in every flesh that is on earth. God said to Noah: "This is the sign of the covenant that I have established between me and all the flesh that is on earth." The sons of Noah who came out of the ark were Sem, Cam and Jafet; Cam is the father of Canaan. These three are the sons of Noah and from these the whole earth was populated.
Deuteronomy 6,4-8
Listen, Israel: the Lord is our God, the Lord is one. You will love the Lord your God with all your heart, with all your soul and with all your strength. These precepts which I am giving you today are fixed in your heart; you will repeat them to your children, you will talk about them when you are sitting in your house, when you walk on the street, when you lie down and when you get up. You will tie them to your hand as a sign, they will be like a pendant between your eyes and you will write them on the jambs of your house and on your doors.
Ezekiel 20,1-29
On the ten of the fifth month, seventh year, some elders of Israel came to consult the Lord and sat before me. This word of the Lord was addressed to me: "Son of man, speak to the elders of Israel and say to them: The Lord God says: Do you come to consult me? As it is true that I live, I will not let you consult. Oracle of the Lord God. Do you want to judge them? Do you want to judge them, son of man? Show them the abominations of their fathers. Tell them: The Lord God says: When I chose Israel and raised my hand and swore by the lineage of the house of Jacob, I appeared to them in the land of Egypt and I swore for them saying: I, the Lord, am your God. Then I raised my hand and vowed to bring them out of the land of Egypt and lead them to a land chosen for them, dripping milk and honey, which is the most beautiful of all the lands. I said to them: Everyone throw away the abominations of your own eyes and do not defile yourself with the idols of Egypt: I am your God. But they rebelled against me and would not listen to me: they did not throw away the abominations of their own eyes and did not they abandoned the idols of Egypt. Then I decided to pour out my fury upon them and to vent my anger against them, in the middle of the land of Egypt. But I did differently in regard to my name, so that it would not be profaned in the eyes of the people among whom they were, since I had declared that I would bring them out of the land of Egypt under their eyes. So I brought them out of Egypt and led them to the desert; 11 I gave them my statutes and made them know my laws, so that the one who observes them lives for them. I also gave them my Sabbaths as a sign between me and them, so that they knew that it is I, the Lord, who sanctify them. But the Israelites rebelled against me in the desert: they did not walk according to my decrees, they despised my laws, which must be observed for man to live, and they always violated my Saturdays. Then I decided to pour out my indignation on them in the desert and to exterminate them. But I acted differently for my name, so that it would not be profaned in the eyes of the people before whom I had brought them out. I had sworn on them in the desert that I would no longer lead them to the land I had assigned to them, land dripping with milk and honey, the most beautiful of all lands, because they had despised my commandments, had not followed my statutes and had desecrated my Saturdays, while their hearts had attached themselves to their idols. However, my eye took pity on them and I did not destroy them, I did not exterminate them all in the desert. I said to their children in the desert: Do not follow the rules of your fathers, do not observe their laws, do not defile yourself with their idols: it is I, the Lord, your God. Walk according to my decrees, observe my laws and put them into practice. Sanctify my Saturdays and be a sign between me and you, so that it is known that it is I, the Lord your God. But even the children rebelled against me, did not walk according to my decrees, did not observe and did not put into practice my laws, which give life to those who observe them; they profaned my Saturdays. Then I decided to pour out my indignation on them and to vent anger against them in the desert. But I withdrew my hand and did differently out of regard for my name, lest it be profaned in the eyes of the people, in whose presence I had brought them out. And in the desert I swore to them, raising my hand, that I would scatter them among the people and scattered in foreign countries, because they had not practiced my laws, indeed, they had despised my decrees, desecrated my Saturdays and their eyes were always turned to the idols of their fathers. Then I even gave them bad statutes and laws they couldn't live for. I made sure that they contaminated themselves in their offerings by passing all their firstborn through the fire, to terrify them, so that they would recognize that I am the Lord. Then speak to the Israelites, the son of man, and say to them: The Lord God says: Again in this your fathers offended me by acting with infidelity towards me: after I had introduced them to the land which, raising my hand, I had sworn to give them, they looked at every high hill, every green tree and there they made sacrifices and brought their provocative offerings: there they deposited their sweet perfumes and poured their libations. I said to them: What is this hill to which you go?