B-Hebrew: The Biblical Hebrew Forum

Once upon a time, methinks, every first letter had a dot placed in it to mark the beginning of the word. With time, Hebrew readers got into the habit of reading the בגדכפת letters differently upon seeing them dotted (which is the bane of spoken Hebrew, leading to all sorts of silly readings by pundits and functionaries under the spell of the "Hebrew Academy".) As the writing technology improved, the initial dot was removed, except for letters susceptible to the dot.
But, the dot was also left in place in cases where a suffix could be mistaken for a next prefix. Here are some examples.

Gen. 3:13 מַה זֹּאת
Gen. 3:14 עָשִׂיתָ זֹּאת
Gen. 14:10 הֶרָה נָּסוּ
Gen. 19:14 קוּמוּ צְּאוּ
2Kings 25:30 נִתְּנָה לּו
Ps. 104:1 גָּדַלְתָּ מְּאֹד
Job 38:5 עָלֶיהָ קָּו
Job. 39:9 הֲיֹאבֶה רֵּים
Proverbs 11:13 מְגַלֶּה סּוֹד
Ruth 1:7 הָיְתָה שָּׁמָּה
Ruth 2:7 אֲלַקֳּטָה נָּא

Isaac Fried, Boston University

Older BH editions are found with four words in which the letter א aleph is dgusha:
Gen. 43:26 וַיָּבִיאּוּ
Lev. 23:17 תָּבִיאּוּ
Job 33:21 רֻאּוּ
Ezra 8:18 וַיָּבִיאּוּ
This, methinks, is a vestige of a more comprehensive ancient system of dgeshim in which every letter following a patah, a hireq, and a qibbuts had this hinting dot in it.

Isaac Fried, Boston University

Also following a suffixed וּ= הוּא, as in Ex. 12:31 קוּמוּ צְּאוּ to guard against the reading קוּם וּצְאוּ.

Isaac Fried, Boston University

Here is another example, Nu. 31:1 וַיְדַבֵּר יְהוָה, אֶל-מֹשֶׁה לֵּאמֹר with a dagesh in the L of לֵּאמֹר, possibly to guard against the blasphemous reading משה אֵל.

Isaac Fried, Boston university