God gave Humanity the Alphabet
When God gave Moses the Ten Commandments on the Mountain of God in Midian aka Mt Sinai, He also gave humanity the alphabet, setting us free from the clumsy pictorial writings available at that time. God blessed all the people of the earth by introducing the alphabet through Moses. Every area of education, including our bible uses the alphabet. Prior to the alphabet there were some types of pictorial writing, like hieroglyphs and cuneiform, which Moses would have known, being educated in Egypt's royal household. These old writing systems were clumsy and often involved hundreds of symbols compared to 20-30 letters in most alphabets. Although some claim there is archeological evidence at the Mountain of God in Midian, which is located in a country dominated by a hostile religion, fortunately our bible contains all the evidence we need to know the alphabet came from God. For example the date God gave Moses the Ten Commandments, 1447-1440 BC is supported by 1 Ki 6:1 (967 + 480 = 1447 BC) and by Jdg 11:26 (1100 + 300 + 40 years in the wilderness = 1440 BC).
Decades ago after learning Greek, God said, "NOW I WANT YOU TO LEARN MY LANGUAGE". In the Hebrew text in school, there was an association between the Hebrew and Greek letters. The English word "alphabet" comes from the first 2 Greek letters "Alpha" "Beta" which come from the first 2 Hebrew letters "Aleph" "Beit". Truly Hebrew is God's language.
God gave Moses the 10 Commandments written by God (Exodus 32:16) in Hebrew on the Mountain of God in Midian where Moses saw the burning bush (Ex 3:1-4) and where God told Moses to return with the Israelites from Egypt (Ex 3:11-12) to "WORSHIP GOD". Note: the Ten Commandments were written on two stone tablets, front and back that were small enough to both be carried by Moses (Exodus 32:15). Only a modern alphabet could fit the Ten Commandments on two stone tablets one man could carry. During the 40 days Moses spent with God on the Mountain of God may be when Moses learned the alphabet from God and we know that during the next 40 years Moses is credited with writing the Torah or the first 5 books of the bible - Genesis, Exodus, Leviticus, Numbers and Deuteronomy. Also during the 40 years of wandering, apparently Moses was teaching the children of Israel how to read and write. In Deuteronomy 27: 1-4 (NI), we discover that Moses and the elders of Israel commanded the people of Israel to obey all the commandments and to use large stones covered with plaster and "Write on them all the words of this law " after they crossed the Jordan. Obviously if they told them to write the words of the Law, they knew how to read and write. Prior to Moses there is no record of the children of Israel or anyone on earth, reading or writing with an alphabet.
Understanding that God gave us the alphabet when He gave us the Ten Commandments, does not explain how it spread to the rest of the world. Remember the Philistines who were frequently giving the Israelites a hard time in the bible and even ruled them (Judges 13:1) at times? They are also called Sea People as they are ancestors of the Greeks and through their conquest were possibly able to spread the alphabet to the Phoenicians and the Greeks. Although this may appear to be a logical explanation, Eupolemus, (also mentioned in 1Maccabees 8:17) a Jewish historian is the most credible source who states in 158 BC that Moses "first wrote the laws for the Jews and then taught the alphabet to the Jews who passed it on to the Phoenicians who passed it on to the Greeks". God loves the world so much He gave humanity the alphabet through His Chosen People when He gave the Ten Commandments to Moses.