Apart from the issue of making songs from pessukim referred to in the comments above, and in the Gemoro Sotah 35a
מפני מה נענש דוד מפני שקרא לדברי תורה זמירות שנאמר זמירות היו לי חוקיך
Why was Dovid punished (by the death of Uza) because he called the words of Torah "songs" as it says "Your statutes were to me as songs ….. "
Tehillim 119 :54
there is an issue with breaking up a pasuk.
Extracted from chaburas.org
The gemara in Ta'anit
and Megilla 22a say that any verse that Moshe did not define, we
cannot define for ourselves (כל פסוקא דלא פסקיה משה אנן לא פסקינן)
While this concept of not breaking verses in half seems to have solid
basis in the gemara, it is interesting that it is not cited in any
context by Rambam, the Tur, or the Shulchan Aruch, and it is barely
dealt with, if at all, by any of the major Rishonim.
There seem to be a number of possible exceptions:
Magen Avraham (O.C.
deals with the issue of splitting up the possuk אָנָּא הֹ הוֹשִׁיעָה
נָּא אָנָּא הֹ הַצְלִיחָה נָּא Psalms 118
into two when saying Hallel and answers (according to Tosefos) that although we agree to the principle of not
defining possukim for ourselves, here it is different because the
possuk is being said by two people. וכתבו התו׳ הא דמפסיקין פסוק
"אנא...” לשנים והא קי״ל דאסור להפסיק באמצע הפסוק שאני הכא שב׳ בני
Daniel Shperber, in Minhagei Yisrael volume 2, cites Rav Reuven
Margoliyot, who suggests that while there is a problem with beginning
a verse and stopping in the middle, it is permitted for one to begin a
verse from the middle and recite it to its conclusion.
In an appendix in volume four of his work, Shperber cites Rav Avraham
Nadav, who offers four possible exceptions to this rule. First, it
does not apply to verses in ketuvim.
Second, it does not apply to verses recited as prayers or
Third, it does not apply if the phrase is only two words long (such as
"Hashem melech"). …..
Finally, Nadav claims that according to the responsa Rav Pe'alim, one
may divide a verse by an 'etnachta,' loosely described as a
cantillation comma, since an etnachta has similarities to the
punctuation used at the end of a verse ('sof pasuk'; for example, both
would render the word 'kesef' as 'kasef').
[I do not understand this.]
The Tzitz Eliezer (9:17:10) cites the Sfat Emet asks how the Hagadah used on Pesach can cite so many fragments of verses (most famously "avadim hayinu")? The Sfat Emet claims that it is not considered to be breaking a verse if the verse contains the words "le'emor" or "v'amarta" – "and you should say" or "so saying." Since the verse describes something tat one should say, one only has to say that part, and does not have to recite as well the command to say it. The Tzitz Eliezer gives a more technical answer, claiming that when the hagadah cites such verses, it is sure to alter a word or two so as to avoid this problem.