ISB ~ John 14 v2

my Father’s house:A similar expression is used in 2:16 for the Jerusalem Temple, hinting that the Father’s house is a heavenly sanctuary (Rev 21:22) perched high above in the heavenly Jerusalem (Gal 4:26; Rev 21:1). This is the eternal dwelling where the glorified angels and saints worship the Lord in the eternal liturgy (Heb 12:22-24; Rev 4-5) (CCC 2795).

many rooms:Similar to the Herodian Temple in Jerusalem, which had several courts for worship, chambers for storage, and living quarters for priests.