Exodus 3:15

זה שמי לעלם THIS IS MY NAME FOR EVER — The last word is written without ו (so that it may be read לְעַלֵּם and it would mean “this is My Name which is to be concealed”) to suggest: Conceal it (this Divine Name), so that it shall not be read exactly as it is written (but should be read as אדני; cf. Pesachim 50a; Exodus Rabbah 3:7). וזה זכרי AND THIS IS MY MEMORIAL (the word may signify “the mention of Me”) — He taught him how the Divine Name should be read. So, too, did David say, (Psalms 135:13) “O Lord, Thy name is for ever (שמך לעולם), O Lord, Thy memorial is throughout all generations (זכרך לדר ודר).

וַיֹּ֩אמֶר֩ ע֨וֹד אֱלֹהִ֜ים אֶל־מֹשֶׁ֗ה כֹּֽה־תֹאמַר֮ אֶל־בְּנֵ֣י יִשְׂרָאֵל֒ יְהֹוָ֞ה אֱלֹהֵ֣י אֲבֹתֵיכֶ֗ם אֱלֹהֵ֨י אַבְרָהָ֜ם אֱלֹהֵ֥י יִצְחָ֛ק וֵאלֹהֵ֥י יַעֲקֹ֖ב שְׁלָחַ֣נִי אֲלֵיכֶ֑ם זֶה־שְּׁמִ֣י לְעֹלָ֔ם וְזֶ֥ה זִכְרִ֖י לְדֹ֥ר דֹּֽר׃

And God said moreover to Moshe, Thus shalt thou say to the children of Yisra᾽el, The Lord God of your fathers, the God of Avraham the God of Yiżĥaq, and the God of Ya῾aqov, has sent me to you: this is my name for ever, and this is my memorial to all generations.