The first twenty letter names are ordinary Slavonic words and read together as connected clauses, from azu buky vede, I know letters, through ritsi slovo tvrido, say the word firmly. That much is not in question. What is in question is what follows from it. One position holds that the names were chosen deliberately so that the recitation of the alphabet would itself be an utterance, a piece of design in keeping with an alphabet made for the reading of scripture. Another holds that the names are largely inherited mnemonic words, that the sense of the sequence is a reading imposed later, and that the point is settled against composition by the fact that the names stop meaning anything at all from the twenty third letter onward. Both positions are held and both can be read.
What would resolve this A ninth or tenth century source that gives the letter names in full as a continuous text, rather than as a list, would show the sequence being read as an utterance at a date close to the alphabet's making. The acrostic alphabet poems of the Old Church Slavonic tradition, which arrange the letters in verse, are the most likely place for such evidence, and a study that separated what those poems inherit from what they compose would bear directly on the question.
OpenOld Church Slavonic philology; Slavic historical linguistics; medieval Slavonic literaturePeter T. Daniels and William Bright (eds.), The World's Writing Systems