Rabbi Akiva, a poor shepherd, learned to read at the age of 40 and became one of the great sages of Israel with the support of his wife Rachel.  He systematized the material that became the Mishnah.  He died on Yom Kippur al kiddush Hashem, murdered by the Romans in Caesaria for teaching Torah.  In his final moments of being tortured, he said the Shema and told his students that he had waited all of his life to fulfill the concept, "You shall love Hashem, your G-d, with all your heart and with all your soul..."