You may be thinking of the book of Psalms, which was, in actuality, the Hebrew songbook used for worship at the Temple and other spiritual occasions.
Psalms (Ephesians 6:19)(Psalm 33:2+3) as indicated by the superscription above Psalms 29, 30, 31 and many others... The Book of Psalms was the Hebrew Songbook, used in the Temple.
The 'book' of Psalms is the original Hebrew songbook, and it is divided by songs. Most have the writer noted above the psalm, usually King David, Asaph or the sons of Korah. Since the songbook was often memorized by the temple singers, there were memory aids noted above certain verses...like letters of the Hebrew alphabet ...(A'leph, Behth, Gimel, Daleth, etc.. in Psalms 37).
The book in the Old Testament that contains 150 hymns used to worship God is the Book of Psalms. It is a collection of poetic songs and prayers that cover a wide range of emotions and themes, often used in religious services and personal devotions.
The book of Psalms IS the songbook used by the nation of Israel in David's time, so that is where David's 'hymns' are.
If you mean in the book of Psalms, there are 150. In addition to these, there are others that are not included in the Old Testament, the so-called psalm 151, 152 plus a few others. These also stem from Hebrew roots of about that time, but never found their way into the Hebrew 'songbook' the psalms.
The book of Psalms is the ancient Hebrew songbook used for the temple singers. "Selah" is believed to be a specific musical notation, explaining what was expected at that point in the song. Many feel that "Selah" stands for a "pause" when singing or for silent meditation, to allow the words which were just sung, to sink in and be more impressive. The Greek Septuagint defined Selah("diapsalma") as "a musical interlude."
A songbook is a type of book that has songs inside.
One thought:The book of Psalms was, actually, the Hebrew songbook, written by faithful worshipers of God, so ALL of it was sung in the temple and on other occasions.We can see evidence of this from many of the 'headings' or 'superscriptions' above many of the Psalms (such as Psalm 3,4, 5, 6, 7, 30, 38, 60, 92, 102) as they provide musical insight and instruction.
Song of Songs is named in that fashion (a book of song), while Psalms most accurately fits the description of commonly being sung.
There are 150 psalms in the Bible. The Book of Psalms consists of 150 psalms
Book one of the book of Psalms contains 41 psalms.