Something that's sanctified is blessed or holy. In many religions, buildings, objects, and people can be sanctified.
A sanctified chalice of wine and sanctified wafers are used in many churches' Holy Communion (or Eucharist) rites. To believers, this means that these things have been blessed by God. Sometimes this adjective describes something that is merely acceptable or respectable, like your brother's sanctified behavior at the dinner table. The Latin root of sanctified is sanctus, "holy."