As Yom Kippur (The Day of Atonement) is ending, near the end of the Neilah service, a prayer is recited: "And seal for a good life all the children of Your covenant." The secret to a good life is embedded within this prayer. The phrase: "Seal for a good life" (Chatom L'chaim tovim) has a numerical value of 613. Because 613 is the total number of commandments in the Bible, it reveals the hidden meaning: if we honor, respect, move towards, and teach our children the 613 commandments, we will have a good life. It is worth noting that the spelling of the word "seal" in the Neilah prayer is different from the spelling of this word in all other prayers. It is because of this unique spelling that the total numerical value of "seal for a good life" equals 613, otherwise the total would have been different.
In the Avinu Malkeinu prayer we pray that God forgive us and have mercy on us: In one of the verses we humbly recite: "Our Father, our King, remember that we are but dust." The numerical value of "Remember that we are but dust" (Zachor ki aphar anachnu) is 728, and the letters that correspond exactly to 728 spell: You shall forget (Tishcach) - this seems to be G-d's comment regarding our humility.