Why Psalm Numbers Differ Between Bibles

Open two Bibles to the same psalm and you may land on two different numbers. The Miserere is Psalm 51 in one book and Psalm 50 in another; the De profundis is 130 here and 129 there. Nothing is missing and nothing was added. The two books are counting the same one hundred fifty psalms in two different ways, and the difference is older than the Church itself.

Two ways of counting the same 150 psalms

The Hebrew text of the Psalter divides the poems one way. The Septuagint — the Greek translation made for Greek-speaking Jews a couple of centuries before Christ — divides a handful of them differently, and the Latin Vulgate followed the Greek. Both systems arrive at exactly 150 psalms; they just draw four of the boundaries in different places, which shifts the numbers of everything in between.

Where the count splits

The Greek joins Hebrew Psalms 9 and 10 into a single psalm, and likewise joins 114 and 115. Going the other way, it splits Hebrew Psalm 116 into two and Hebrew Psalm 147 into two. The net effect: most psalms from 10 through 146 sit one number lower in the Greek and Latin count, while the first nine and the last three carry the same number in both systems. A few landmarks, in Hebrew and then Greek numbering:

• The shepherd psalm — 23 in Hebrew numbering, 22 in Greek and Latin.
• The Miserere — 51 in Hebrew numbering, 50 in Greek and Latin.
• The shelter of the Most High — 91 in Hebrew numbering, 90 in Greek and Latin.
• The De profundis — 130 in Hebrew numbering, 129 in Greek and Latin.

Why modern Catholic Bibles use the Hebrew numbers

Because the Vulgate shaped Catholic life for over a millennium, generations of Catholic books — the Douay-Rheims Bible, old missals and prayer books — carry the Greek and Latin numbers. That is why an older holy card may call the De profundis Psalm 129. Modern Catholic translations and lectionaries, however, use the Hebrew numbering, often printing the older number in parentheses. The reasons are practical: it matches the Hebrew text that translators now work from, and it matches the numbers most readers meet everywhere else, so a reference like Psalm 23 means the same thing to everyone. Adorantis uses the Hebrew numbering throughout, the same count as most modern Catholic Bibles.

A one-line test for any book

Look up the shepherd psalm. If “The LORD is my shepherd; I shall lack nothing.” (Psalm 23:1) appears under the number 23, the book uses the Hebrew count. If the same words appear as Psalm 22, you are holding the Greek and Latin numbering — common in older Catholic editions and in texts quoting the Vulgate. One verse settles it every time.