In that part of the book of my memory before which little can be read, there is a heading, which says: “Incipit vita nova: Here begins the new life.”

[In quella parte del libro de la mia memoria dinanzi a la quale poco si potrebbe leggere, si trova una rubrica la quale dice: Incipit vita nova.]

Dante Alighieri (1265-1321) Italian poet

La Vita Nuova [Vita Nova; The New Life], ch. 1 (c. 1294, pub. 1576) [tr. Kline (2002)]
    (Source)

Opening sentence of the work.

There is some scholarly disagreement as to whether the title means "the new life" or "the early life." Reynolds translates the Latin phrase here as "Here begins the period of my boyhood," as explained here. Most scholars prefer the "new life" interpretation, with some caveats.

(Source (Italian)). Alternate translations:

In that part of the book of my memory before the which is little that can be read, there is a rubric, saying, Incipit Vita Nova.
[tr. Rossetti (c. 1847; 1899 ed.)]

In that part of the book of my memory, anterior whereto is little that can be read, stands a rubric, which says : -- "Incipit Vita Nova. Here beginneth the New Life."
[tr. Martin (1862)]

In that part of the book of my memory before which little can be read is found a rubric which says: Incipit Vita Nova [The New Life begins].
[tr. Norton (1867), "Proem"]

In the book of my memory, after the first pages, which are almost blank, there is a section headed Incipit vita nova.
[tr. Reynolds (1969)]

In that part of my book of memory before which there would be little to read is found a chapter heading which says: “Here begins the new life.”
[tr. Musa (1971)]

In my Book of Memory, in the early part where there is little to be read, there comes a chapter with the rubric: Incipit vita nova.
[tr. Hollander (1997)]

In that part of the book of my memory before which little may be read is found a rubric which says: "The new life begins."
[tr. Appelbaum (2006)]

In the book of my memory -- the part of it before which not much is legible -- there is the heading Incipit vita nova.
[tr. Frisardi (2012)]

There is a poetic version of this opening sentence which I have not been able to source, but has become extremely popular in wedding vows and other pronouncements of love, and is usually presented as Dante's own work:

In that book which is
My memory ...
On the first page
That is the chapter when
I first met you
Appear the words ...
"Here begins a new life."

Dante's first meeting with Beatrice (when he was nine years old) is described in the following paragraph, but is not part of this opening sentence. This chapter is also part of the prose portion of the work, not a poem.