第三条（非課税とされる通勤手当に関する経過措置）
Supplementary Provisions, Article 3Transitional Measures Concerning Commutation Allowances Treated as Nontaxable
The provisions of Article 20-2 (Commutation Allowance Treated as Nontaxable) of the New Order apply to the commutation allowance prescribed in that Article that is to be received on or after January 1, 1989 (excluding any such commutation allowance that is paid additionally as the difference in the commutation allowance received before that day), and the provisions then in force continue to govern the commutation allowance prescribed in that Article that is to be received before that day (including any such commutation allowance that is to be received on or after that day and is paid additionally as the difference in the commutation allowance received before that day).
With regard to the application of the provisions of Part IV, Chapter II, Section 1 (Obligation to Withhold Taxes on Salary Income or Tax Amount Collected) of the Income Tax Act to a commutation allowance referred to in the preceding paragraph that is to be received on or after January 1, 1989 and that was received before the day of enforcement of this Cabinet Order (hereinafter referred to as the "Effective Date"), the provisions then in force continue to govern, notwithstanding Article 20-2 of the New Order and the preceding paragraph.
略称規定附則第二条第一項
別段の定めがあるものを除き、改正後の所得税法施行令（以下「新令」という。）の規定は、平成元年分（昭和六十四年一月一日から平成元年十二月三十一日までの期間に係る年分をいう。）以後の所得税について適用し、昭和六十三年分以前の所得税については…
わかりやすく言うと
平成元年政令第九十二号によって改正された後の所得税法施行令のことです。
略称規定附則第三条第二項
昭和六十四年一月一日以後に受けるべき前項の通勤手当でこの政令の施行の日（以下「施行日」という。）前に受けたものに係る所得税法第四編第二章第一節（給与所得に係る源泉徴収義務又は徴収税額）の規定の適用については…
わかりやすく言うと
この附則が属する改正政令（平成元年政令第九十二号）が施行される日のことです。