Upon the completion of the Mishkan, we are told: ‘Moshe saw the entire work and lo! they had done it (וְהִנֵּה עָשׂוּ אֹתָהּ); as God had commanded, so had they done (כֵּן עָשׂוּ); and Moshe blessed them’ (Shemot 39:43). This verse is obviously puzzling since we are twice told that the people did what was necessary to build the Mishkan. Moreover, while the verse informs us that Moshe blessed the people, we are not informed of the substance of this blessing.
To answer the second question first, Rashi – while quoting the Midrash – informs us that Moshe blessed the people with the words: ‘יְהִי רָצוֹן שֶׁתִּשְׁרֶה שְׁכִינָה בְּמַעֲשֵֹה יְדֵיכֶם – May the Shechinah rest in the work of your hands’, then adding ‘וִיהִי נֹעַם אֲ-דֹנָי אֱלֹקינוּ עָלֵינוּ וּמַעֲשֵׂה יָדֵינוּ כּוֹנְנָה עָלֵינוּ וכו’ – May the pleasantness of my Lord, our God, be upon us and [make] the work of our hands etc.’ (Tehillim 90:17). Yet, here too, we have a form of repetition, with both statements appearing to convey the same sentiment. Why would Moshe need to bless the people with the same blessing twice?!
To make sense of both the verse and the Rashi, we must turn to the Maharsham (in his Torah commentary Techelet Mordechai) who himself begins his explanation with reference to the Alshich. When God initially commanded that the Mishkan be constructed, He instructed Moshe to tell the people ‘וְשָׁכַנְתִּי בְּתוֹכָם וְעָשׂוּ לִי מִקְדָּשׁ – they shall make Me a sanctuary, and I will dwell among them’ (Shemot 25:8), and according to the Alshich, this verse refers to two forms of Miskhan: וְעָשׂוּ לִי מִקְדָּשׁ refers to the physical Mishkan that would reside in the centre of the Israelite camp, while the words of וְשָׁכַנְתִּי בְּתוֹכָם refer to the duty on each and every Jew to make themselves holy and become a personal Mishkan.
Based on this, the Maharsham explains that the first phrase in the above verse of and lo! they had done it (וְהִנֵּה עָשׂוּ אֹתָהּ) refers to the fulfilment of the commandment to build the Mishkan, while the second phrase so had they done (כֵּן עָשׂוּ) refers to the fulfilment of the commandment for each person to make themselves into a personal Mishkan.
Having then drawn this distinction, the Maharsham explains that the first of the two blessings recorded by Rashi of ‘יְהִי רָצוֹן שֶׁתִּשְׁרֶה שְׁכִינָה בְּמַעֲשֵֹה יְדֵיכֶם – May the Shechinah rest in the work of your hands’ refers to the physical Mishkan, while the second blessing of ‘וִיהִי נֹעַם אֲ-דֹנָי אֱלֹקינוּ עָלֵינוּ וּמַעֲשֵׂה יָדֵינוּ כּוֹנְנָה עָלֵינוּ – may the pleasantness of my Lord, our God, be upon us and [make] the work of our hands etc.’ refers to the inner Mishkan of all those involved. Thus, Moshe’s blessing was not just in praise for the construction of the physical Mishkan, but also in recognition of the development of the inner Mishkan in everyone involved.
Reflecting on this idea we learn that in just the same way that we have a Chanukat HaBayit when houses are built, shuls are constructed, schools are created and Tabernacles are completed, it is no less important to celebrate when someone spiritually grows, when they resist their yetzer hara, when they dedicate their life to chessed and when they live a life of Kiddush Hashem, because to be a true Jew, it is no less important to value the building of the inner Mishkan within each of us.