Sefer HaBahir 53

1[Rabbi Berachiah continued,] "And why is it called gold [זהב]? Since three traits are included in it: 1) male, which is zayin; 2) the soul [נשמה], which is the heh and [includes] the five [ה] names of the soul, ruach [רוח], chayah [חיה], yechidah [יחידה], nefesh [נפש], and neshama [נשמה] — why was she [the soul] made in five? To be a throne to the zayin, as is written, 'For a higher one is protected by a higher one' (Ecclesiastes 5:7) — and, 3) the bet establishes them, as is said, In [ב] the beginning, created' (Genesis 1:1)."