The commandment to love other people is given in the Torah, which states, "Love your neighbor like yourself" (Leviticus 19:18). The Torah's commandment to love God "with all your heart, with all your soul and with all your might" (Deuteronomy 6:5) is taken by the Mishnah (a central text of the Jewish oral law) to refer to good deeds, willingness to sacrifice one's life rather than commit certain serious transgressions, willingness to sacrifice all of one's possessions, and being grateful to the Lord despite adversity (tractate Berachoth 9:5). Rabbinic literature differs as to how this love can be developed, e.g., by contemplating divine deeds or witnessing the marvels of nature. As for love between marital partners, this is deemed an essential ingredient to life: "See life with the wife you love" (Ecclesiastes 9:9). The biblical book Song of Solomon is considered a romantically phrased metaphor of love between God and his people, but in its plain reading, reads like a love song. The 20th-century Rabbi Eliyahu Eliezer Dessler is frequently quoted as defining love from the Jewish point of view as "giving without expecting to take" (from his Michtav me-Eliyahu, Vol. 1).