The Torah Text
One of the laws in Deuteronomy reads: “You shall set aside every year a tenth part of all the yield of your sowing that is brought from the field” (Deut. 14:22). The choice to give a tenth gives rise to a mathematical-spiritual aside on special numbers from our teacher.
Ibn Ezra’s Teaching
ודע אם תחל ממעל הנה האחד ראש ואם ממטה הנה העשירי וזה סוד הבכור והמעשר ודע כי האחד איננו בחשבון וכן העשירי כי הוא כנגד האחד כי הוא ראש למחברת השנית וסוף למחברת הראשונה וכל שרש בחשבון סמוך אליו מפניו ומאחריו ובעבור היות האחד והעשרה עיקריים והאמצעיים חמשה וששה הם הנקראים עגולים על כן אותיות הנח הם אלה הארבעה ומהם אותיות השם הנכבד והנורא
Deuteronomy 14:22 … Note. If you start from the top [i.e. at the beginning of the numbers], then one is the first number. If you start from below [i.e. at the bottom of the first ten numbers], then, behold, ten is the first number [i..e the first of the tens]. This is the secret of the first-born and the tithe.
Observe. The number one does not depend on a sum. The number ten is similar. It is the counterpart of one because it is the beginning of the second series of numbers [i.e. the first of the tens]. It is also the end of the first series [i.e. one through nine]. All parts of sums are connected to ten in front and in back [i.e. before and after ten].
The numbers one and ten are the main numbers; the middle numbers, five and six, are called the round numbers. These four numbers therefore form the silent letters. They are also the letters that form the glorious and awe-inspiring name. (Translation: Strickman and Silver)
Reflections for the Path
One is of course a special number because it is the first number – no sum makes it up, it is whole and represents unified wholeness. Ten is a partner to one in that it is the final step in the first ten numbers, and from that point on begins a new category of counting, with every number from ten onward being a multiple of ten or with ten plus one of the first nine numbers.
Five and six are interesting – when five is squared, cubed, or raised to the nth power, it will always result in a number whose last digit is five, and the same is true of six.
The first letter of the Hebrew alphabet is the silent aleph. The fifth letter is the aspirated hey (sounds like an out-breath when you can hear it at all) and is used silently to represent the ah vowel sound. The sixth letter is the vav, which is often used to represent the oo or oh vowel sounds. The tenth letter is yud, which is often used to represent the ee or ay vowel sounds. Together these letters represent the power of the invisible, the ever changing vowels which animate the other letters. They are also the letters of God’s name, most commonly found as yud hey vav hey YHVH but in Exodus 3:14 all four letters are present in “ehyeh asher ehyeh” אֶהְיֶה, the name God shares with Moses. “I am what I am” or “I am always-becoming”. So the vowel letters, the numbers they represent in the alphabet, and the divine invisible all align in powerful ways.