Before learning about brachos, the Shulchan Aruch wants us to know a little about the meaning of a brachah, and in particular, the meaning of the various names of Hashem. Indeed, the most important aspect of ‘kavanah’ (intent) of any bracha or tefilah is in understanding the words we are saying. And while this may not be so easy for everyone all the time, we must at least know what we mean when we utter one of the Divine names.
In every bracha, three names are used:
1) The name of ‘Adnus’ (lit. mastership) – as in ‘A-do-noi’. (Note: This name is used both when it is spelled this way and when it is spelled in the manner of the ‘Shem Havaya’ – see next.)
2) The “ineffable” name, referred to as the ‘Shem Havaya’ (lit. the name of “Existence”), based upon a re-ordering of the letters in that name – ‘yud’ ‘hay’ ‘vav’ and ‘hei’. This name is written but not pronounced. We should see and think of this name when we read it, but we should pronounce it as the previous name, A-do-noi. (Note: The Sages teach that we are forbidden to pronounce this name the way it is written, and that whoever does so will lose his portion in the World to Come!)
3) The name of ‘elokus’ (lit. Al-mighty), as in ‘Elokeinu’ or ‘Elokim’ (Ed. in pronunciation, the “k” sound is replaced with an “h” sound, as you know.)
The Shulchan Aruch teaches us that for the name ‘Adnus’, one should think of Hashem’s Mastery over all of existence; for the ‘Shem Havaya’, one should think about how Hashem was, is and will always be, and for the name of ‘Elokus’, one should think about how Hashem is all-powerful, all-capable and is the source of all other powers. (Note: Thus, when the ‘Shem Havaya’ is written and ‘Adnus’ is pronounced, there are actually two different ‘kavanos’ one should have, but primarily the meaning of ‘Adnus’.)
In general, one should try never to allow a bracha to simply roll mindlessly from his lips. Citing the holy work, Sefer Chassidim (Book of the Pious Ones), Mishneh Berura writes that when making a bracha, a person should think about how wondrous of Hashem to have given us a pleasurable food or experience or to have commanded us to connect to Him through the performance of mitzvos. The Prophet Yeshaya (Isaiah) criticized his generation for honoring Hashem with their mouths and lips, while from their hearts He was distant! This, said the Prophet, causes great anger and disappointment to Hashem!
Finally, the Mishnah Berura emphasizes that the name ‘Adnus’ should be pronounced correctly, with the vowel ‘kamatz’ (‘oi’ rather than ‘ai’), and with the emphasis on the last syllable (‘noi’).