This could not possibly be more clear:
From Royal decree 743:
"Section 5 Income tax under Part 2 of Chapter 3 in Title 2 of the Revenue Code shall be exempted for a foreigner categorised as Wealthy Global Citizen, Wealthy Pensioner, or Workfrom-Thailand Professional who is granted a Long-Term Resident Visa under immigration law for assessable income under section 40 of the Revenue Code derived in the previous tax year from an employment, or from business carried on abroad, or from a property situated abroad, and brought into Thailand."
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