וְנָתַתָּ֞ה אֶת־מִזְבַּ֤ח הַזָּהָב֙ לִקְטֹ֔רֶת לִפְנֵ֖י אֲר֣וֹן הָעֵדֻ֑ת וְשַׂמְתָּ֛ אֶת־מָסַ֥ךְ הַפֶּ֖תַח לַמִּשְׁכָּֽן׃
And thou shalt set the golden altar for incense before the ark of the testimony, and put the screen of the door to the tabernacle.
Read kabbalistic (mystical) interpretation of Exodus 40:5: and classical mystical sources.