瑜伽師地論略纂 9.73

9.73

論云「終不退轉，棄捨所學」者，第五、明得決定智故，於所學中必不退轉，棄捨所學也。

Where the treatise says, "One never regresses or abandons what one has trained in": this is the fifth, clarifying that because one has attained definitive wisdom, one will certainly not regress from or abandon what one has trained in.