Ha csak kicsit vannak lekopva a betűk, elvileg nem probléma.
If the letters of the words were erased slightly, if their impression is still recognizable a little bit such that a child who's neither a genius nor a simpleton is able to read it, it's permitted to pass over it with a quill to improve the writing and renew it, and this is not considered [written] out of order.
A könnyítő vélemény.
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Szín kapcsán a tefilin és a széfer Tóra kapcsán hasonlót ír.
They should be written in black ink, whether or not the ink contains gallnut juice (tannic acid). Rema: It is preferable to be careful to write only with ink made of smoked wood or oil (ie. the collected vapors which were then dried and pulverized) soaked in gallnut juice [Maharil - Siman 119] and as is explained in Yoreh Deah - Siman 271.) If he wrote even one letter in a different color or in gold, the tefillin are invalid. If he gilded the letters, he can remove the gold and leave the bottom letters and the tefillin will be valid. But if he gilded [even] one letter of the Divine Names, there is no solution because removing the gold would constitute erasing a Divine Name [which is forbidden].
A Torah Scroll must be copied with black ink made of the smoke of oils mixed in gall-nut water. (preferably one should be careful to make the ink only with ingredients that come from trees)(Implied by Zohar Terumah 72a) If he copied with a solution of gall-nut and vitriol [this mixture creates a black ink] it is fit for use, but [this is] not [so] with the rest of the colors like red, green etc. If he wrote a single letter in the other colors or in gold it is unfit for use. Rema: Ergo it is forbidden to copy any of the 24 books [of the Hebrew bible] not in black ink (Rabbeinu Yeruham quoting ibn yarhi) There are those who say that we only require black ink for a Torah Scroll (Mordekhai ה"ק).
Ez utóbbiról írja a Kol Jáákov a szigorítást:
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