No, one can't scatter a person's ashes in the sea or the air, nor keep the urn in your home. I have heard such things many times - and, I saw the family grave somewhere on a big lot and compound... .
In 1963, shortly after Vatican II the Catholic church "determined that cremation was no longer absolutely forbidden. Only with the New Code of Canon Law (1983) did the Church lift the prohibition.
Monsignor Joselito C. de Asis, JCD, assistant secretary general of the Catholic Bishops Conference of the Philippines and a canon lawyer, who completed his doctoral studies in Rome informed, that the CBCP has issued a number of guidelines, such as follows:
- Cremation may take place before or after the funeral mass.
- After cremation, the ashes are to be placed in a worthy urn and brought reverently to the place of burial.
- The cremated remains should be buried in a grave, mausoleum or columbarium. The practice of scattering the ashes in the sea or from the air is not keeping with the Church's norm regarding the proper disposal of the remains of the dead.
- The urn holding the ashes should not be kept permanently at home for family altar... .