If humans build the third temple, would the builders be required to be cleared of "purity standards" for the project?

Question

We are taught that when we came to Israel, King David could not build the temple because he had blood on his hands. Though he was acting under divine command and in the interest of the nation, he still was not allowed to undertake this task. Solomon was given that responsibility and he ultimately completed it.

My question relates to the reasoning for David's inability to build the temple.

In the event that we did decide to build the third temple, would the issue of bloodshed or other impurities come up in the vetting of those who would build the temple?

My assumption is that some level of ritual purity "standard" would need to exist. What that standard is and how we would come to a determination for who does or doesn't qualify is beyond my knowledge. I simply relate this to how there are certain areas of the Beit Hamikdash which only the priests could enter. This makes me think the entire process would need to be overseen by authorities to maintain a baseline "purity" for the entire location during the building process.

Is there any sort of standard we know of regarding what qualifies or disqualifies the would-be builders of the third temple?

Has such a standard or process even been theorized in Jewish sources? Or is it so oddly specific that no one ever considered how we might begin such a process?

Answer 1

The issue is adressed directly in the end of the tractate Eiruvin:

תָּנוּ רַבָּנַן: הַכֹּל נִכְנָסִין בַּהֵיכָל לִבְנוֹת לְתַקֵּן וּלְהוֹצִיא אֶת הַטּוּמְאָה, וּמִצְוָה בְּכֹהֲנִים. אִם אֵין שָׁם כֹּהֲנִים — נִכְנָסִין לְוִיִּם, אֵין שָׁם לְוִיִּם — נִכְנָסִין יִשְׂרְאֵלִים. וְאִידֵּי וְאִידֵּי, טְהוֹרִין — אִין, טְמֵאִין — לָא. אָמַר רַב הוּנָא: רַב כָּהֲנָא מְסַיַּיע כָּהֲנֵי, דְּתָנֵי רַב כָּהֲנָא: מִתּוֹךְ שֶׁנֶּאֱמַר ״אַךְ אֶל הַפָּרוֹכֶת לֹא יָבֹא״, יָכוֹל לֹא יְהוּ כֹּהֲנִים בַּעֲלֵי מוּמִין נִכְנָסִין בֵּין הָאוּלָם וְלַמִּזְבֵּחַ לַעֲשׂוֹת רִיקּוּעֵי פַחִים — תַּלְמוּד לוֹמַר ״אַךְ״ — חִלֵּק: מִצְוָה בִּתְמִימִים, אֵין שָׁם תְּמִימִים — נִכְנָסִין בַּעֲלֵי מוּמִין. מִצְוָה בִּטְהוֹרִין, אֵין שָׁם טְהוֹרִין — נִכְנָסִין טְמֵאִין. אִידֵּי וְאִידֵּי, כֹּהֲנִים — אִין, יִשְׂרְאֵלִים — לָא.

The Sages taught in a baraita: It is permitted for everyone to enter the Sanctuary to build, to repair, or to remove impurity from inside. However, wherever possible, the mitzva is for these tasks to be performed by priests. If no priests are available, Levites enter; if no Levites are available, Israelites enter. In both cases, if they are ritually pure, yes, they may enter, but if they are impure, no, they may not enter the holy place. Rav Huna said: Rav Kahana, who was a priest, supports priests by emphasizing their special sanctity. As Rav Kahana taught in a baraita: Since it is stated with regard to a priest who has a physical blemish, “Only he shall not go in unto the veil, nor come near to the altar, because he has a blemish, that he profane not My holy places; for I am the Lord who sanctifies them” (Leviticus 21:23), I might have thought that priests with blemishes may not enter the area between the Entrance Hall and the altar to manufacture beaten plates of gold for the Holy of Holies. Therefore, the verse teaches “only” as an expression of exclusion, which means that there is a distinction here: Although the mitzva should be performed with unblemished priests ab initio, if no unblemished priests are available, blemished ones may enter. Likewise, it is the duty of ritually pure priests; if no pure priests are available, impure ones may enter. In both cases, if they are priests, yes, they may enter, but if they are Israelites, no, they may not enter the holy place. According to Rav Kahana, ritually impure priests take precedence over ritually pure Israelites.

To summarize, preferably only ritually pure unblemished cohanim should do the building, but if they are unavailable, leviim or yisraelim, even those who are not ritually pure, may build.

Codified by the Rambam.

Answer 2

1. While Kind David was prevented from building the first Temple because he had shed much blood, it had nothing to do with impurity (Tum'ah).

How do I know this?

Firstly, King David wasn't planning on becoming a builder. At the time he was already elderly and was very busy running a country. Clearly he was going to have workers do the actual building.

Secondly, there are clearly defined ways to change from a state of impurity to one of purity. King David could have simply purified himself, if impurity was an issue.

2. During the actual building, the unfinished Temple has no sanctity. That only arrives with its inauguration.

3. Buildings don't become impure; even if there are built by impure people with impure instruments, the building - since it's connected to the ground - is not impure. I'm not even sure if most building materials are capable of becoming impure: sand, bricks and the like.

4. The only issue I can think of is how they are going to enter the Temple Mount compound. There are certain areas that one may not enter in a state of impurity.

As to who would build the third Temple? All I can think of is that anybody learning Torah is discouraged from joining, as we learn in Megila 16b, as well as all school kids learning Torah, as we learn in Shabbat 119b.

So that leaves those people who wouldn't be spending their spare time learning Torah.