It is stated in the parashah of tzitzis:
דַּבֵּר אֶל־בְּנֵי יִשְׂרָאֵל וְאָמַרְתָּ אֲלֵהֶם וְעָשׂוּ לָהֶם צִיצִת
"Speak to Bnei Yisrael and say to them that they shall make for themselves tzitzis.”
Rabbeinu, the Maharal, notes that as is well known, dibbur is an expression of severity, whereas amirah is an expression of gentleness. We must therefore understand why the verse begins with the language of dibbur "daber!” (“speak!”) and concludes with the language of amirah "veʼamarta aleihem” (“And you shall say to them.")
Our masters, the Baalei HaTosafos, in Maseches Bava Basra (74a, s.v. Piskei), discuss whether one provides tzitzis for the deceased. Tosafos brings proof from an incident related by Rabbah bar bar Chanah. He said: “He (an Ishmaelite merchant) said to me: 'Come, and I will show you those (the generation) who died in the wilderness.' I went and saw them. They appeared like people who had drunk wine, and their faces were radiant. They were lying on their backs, and one of them had a raised knee. The [leg was so tall that the] merchant passed beneath his knee while riding a camel with an upright spear in his hand, yet he did not touch it. I cut off one corner containing techeles from one of them, and afterward we were unable to leave. The merchant said to me: ‘Did you perhaps take something from them? Return it! We have a tradition that whoever takes anything from them cannot depart.' I went and returned it, and then we were able to leave."
When I came before the Sages, they said: “Every Abba is a donkey, and every bar bar Chanah is a fool! For what [halachic] purpose did you do this? [Surely it was] to determine whether the tzitzis in the wilderness were made according to Beis Shammai or according to Beis Hillel” [who were in a disagreement regarding the number and length of the strings]. "You should have counted the strings and counted the windings [without taking the corner itself!]” From here, Tosafos initially brings proof that the dead wear tzitzis.
However, Tosafos ultimately rejects this proof. It is possible that the dead do not wear tzitzis at all. Rather, the generation of the wilderness was unique, for they entered their graves while still alive, as the Midrash relates: Every year on the eve of Tishah B'Av, they would go into their graves while still alive, and a Heavenly Voice would proclaim: “Let the living separate from the dead." Whoever did not [later] rise, remained in his grave. Since they entered their graves alive, they still had tzitzis upon them even after their passing.
Based upon these words of Tosafos, Rabbeinu explains our passage. The section of tzitzis was given after the decree resulting from the sin of the spies, namely, that Bnei Yisrael would remain in the wilderness for forty years and would all die there. This is precisely what the Torah alludes to. On the one hand, the decree is a harsh dibbur: they would die in the wilderness and not enter the Land. On the other hand, there is also ve'amarta, a gentle expression. For the manner of their passing would be that they entered their graves while still alive, and through this they would attain a unique distinction: They would “make for themselves tzitzis upon the corners of their garments throughout their generations” (“yaʼasu lahem tzitzis al kanfei vigdeihem ledorosam”). Forever! For they would continue to fulfill the mitzvah of tzitzis even after their passing, for generations without end. This is the amirah, the gentle aspect within their death in the wilderness.
Rabbeinu concludes that this idea is hinted to in the verse itself. If we take the phrase: צִיצִית עַל כַּנְפֵי בִגְדֵיהֶם לְדֹרֹתָם ‘tzitzis al kanfei bigdehem ledorosum" (“tzitzis upon the corners of their garments throughout their generations”), the final letters spell לַמַּתִים “lamesim” (“for the dead”). In other words, those who died in the wilderness too would possess the mitzvah of tzitzis.
