Wearing Tekhelet in Our Times
Question
Why should one not wear tekhelet based on the principle that in cases of doubt regarding a Torah obligation, one should be stringent?
Answer
The response of our teacher, the Rabbi shlita
A. From the Gemara it appears that not every sea creature called a chilazon is valid; rather, one needs the specific chilazon from which tekhelet is produced. [See Menachot 44; Tosefta Menachot, chapter 9].
B. The identifying signs given by Chazal do not fit the purpura mollusk very well. Its body is not similar to the sea, and its form is not similar to a fish. Likewise, the blood of the purpura is not used for dyeing tekhelet. [Although, admittedly, one can offer forced explanations to resolve this].
C. There is a well-known discussion as to whether the color of the purpura is purple or blue.
D. The purpura chilazon is very common, and not only in the portion of Zevulun. [Although this proof can be rejected].
[E. I heard from our teacher, Rabbi Amram Fried shlita, that the sages of Kabbalah said that the Samech-Mem attaches itself to one who wears kala ilan, and this alone is a reason to refrain from wearing something that is doubtful].
In practice: there is no conclusive proof that what is called tekhelet today is the true tekhelet. And although every point can be answered in some way, since there are no conclusive proofs for this and there are halachic uncertainties regarding the matter, one should remain as before and not wear tekhelet, in accordance with the practice until today.