Or (with the Septuagint and Vulgate), Lest she should ponder (or "She ponders not") the way of life, her paths move to and fro (unsteady as an earthquake); she knows not. The words describe with a terrible vividness the state of heart and soul which prostitution brings upon its victims; the reckless blindness that will not think, tottering on the abyss, yet loud in its defiant mirth, ignoring the dreadful future.

Lest thou shouldest ponder - To prevent thee from reflecting on thy present conduct, and its consequences, her ways are moveable - she continually varies her allurements.
Thou canst not know them - It is impossible to conceive all her tricks and wiles: to learn these in all their varieties, is a part of the science first taught in that infernal trade.

Lest thou shouldest ponder the path of life, her ways are (d) moveable, [that] thou canst not know [them].
(d) She has always new means to allure to wickedness.

Lest thou shouldest ponder the path of life,.... Consider and meditate which is the way to get out of her hands and ways, and escape death, and obtain eternal life; lest those she has drawn into her wicked course of life should be religiously inclined, and think of quitting such a course, and inquire after the way of life and salvation; and be weighing in their minds which is most eligible, to continue with her whose feet lead to death, or to take the path of life: to prevent all this, if possible,
her ways are movable: she appears in different shapes; changes her dress and habitation; makes use of a thousand arts to ensnare men, to entangle their affections, and retain them in her nets; she first puts them upon one thing, and then on another; she leads them into various mazes and labyrinths of sin, till they have lost all sense of religion, and sight of the path of life;
that thou canst not know them; her ways, arts, and devices. Or, "thou canst not know" (k); that is, the way of life, or how to get out of her ways into that. Or, "thou knowest not"; where she goes, whither she leads thee, and what will be the end and issue of such a course of life. The Targum understands it, and so some other interpreters, of the harlot herself, paraphrasing the whole thus;
"in the way of life she walks not; her ways are unstable, and she knows not''
the way of life, nor where her ways will end; or, "cares not" (l) what becomes of her. And so, in like manner, the former part of the verse is understood and interpreted, "lest she ponder the path of life" (m); or as others, "she does not ponder the path of life" (n); The ways of the antichristian harlot are with all deceivableness of unrighteousness; and her chief care is to keep persons in ignorance, and from pondering the path of life or true religion, and to retain them in her idolatry, 2-Thessalonians 2:9.
(k) "non scires", Cocceius; "non cognosces", Baynus. (l) "Haud curat", Schultens. (m) "iter vitae ne forte libraverit", Schultens. (n) "Viam vitae non appendit, vel ponderat", Gejerus; so Luther; "iter vitae non expandit", Noldius, p. 249. No. 2008.

her ways . . . know--Some prefer, "that she may not ponder the path of life," &c.; but perhaps a better sense is, "her ways are varied, so as to prevent your knowledge of her true character, and so of true happiness."

If we try to connect the clause beginning with פּן with 5b as its principal sentence: she goes straight to the abyss, so that by no means does she ever tread the way of life (thus e.g., Schultens), or better, with 6b: never more to walk in the way of life, her paths fluctuate hither and thither (as Gr. Venet. and Kamphausen in Bunsen's Bibelwerk, after Bertheau and Ewald, translate); then in the former case more than in the latter the difference of the subject opposes itself, and in the latter, in addition, the לא תדע, only disturbing in this negative clause. Also by the arrangement of the words, 6a appears as an independent thought. But with Jewish expositors (Rashi, Aben-Ezra, Ralbag, Malbim, etc.) to interpret תּפּלּס, after the Talmud (b. Mod katan 9a) and Midrash, as an address is impracticable; the warning: do not weigh the path of life, affords no meaning suitable to this connection - for we must, with Cartwright and J. H. Michaelis, regard 6a as the antecedent to 6b: ne forte semitam vitae ad sequendum eligas, te per varios deceptionum meandros abripit ut non noveris, ubi locorum sis; but then the continuation of the address is to be expected in 6b. No, the subject to תפלם is the adulteress, and פּן is an intensified לא. Thus the lxx, Jerome, Syr., Targ., Luther, Geier, Nolde, and among Jewish interpreters Heidenheim, who first broke with the tradition sanctioned by the Talmud and the Midrash, for he interpreted 6a as a negative clause spoken in the tone of a question. But פּן is not suitable for a question, but for a call. Accordingly, Bttcher explains: viam vitae ne illa complanare studeat! (פּלּס in the meaning complanando operam dare). But the adulteress as such, and the striving to come to the way of life, stand in contradiction: an effort to return must be meant, which, because the power of sin over her is too great, fails; but the words do not denote that, they affirm the direct contrary, viz., that it does not happen to the adulteress ever to walk in the way of life. As in the warning the independent פּן may be equivalent to cave ne (Job 32:13), so also in the declaration it may be equivalent to absit ut, for פּן (from פּנה, after the forms בּן = Arab. banj. עץ = Arab. 'aṣj) means turning away, removal. Thus: Far from taking the course of the way of life (which has life as its goal and reward) - for פּלּס, to open, to open a road (Psalm 78:50), has here the meaning of the open road itself - much rather do her steps wilfully stagger (Jeremiah 14:10) hither and thither, they go without order and without aim, at one time hither, at another time thither, without her observing it; i.e., without her being concerned at this, that she thereby runs into the danger of falling headlong into the yawning abyss. The unconsciousness which the clause לא תדע esu expresses, has as its object not the falling (Psalm 35:8), of which there is here nothing directly said, but just this staggering, vacillation, the danger of which she does not watch against. נעו has Mercha under the ע with Zinnorith preceding; it is Milra [an oxytone] (Michlol 111b); the punctuation varies in the accentuations of the form without evident reason: Olsh. 233, p. 285. The old Jewish interpreters (and recently also Malbim) here, as also at Proverbs 2:16, by the זרה [strange woman] understand heresy (מינות), or the philosophy that is hostile to revelation; the ancient Christian interpreters understood by it folly (Origen), or sensuality (Procopius), or heresy (Olympiodorus), or false doctrine (Polychronios). The lxx, which translates, Proverbs 5:5, רגליה by τῆς ἀφροσύνης οἱ πόδες, looks toward this allegorical interpretation. But this is unnecessary, and it is proved to be false from Proverbs 5:15-20, where the זרה is contrasted with the married wife.

Lest - To prevent thy serious consideration. Moveable - She transforms herself into several shapes, and has a thousand arts to ensnare. Know - Thou canst not discover all her practice.