Are your parents living? He said: Yes. Thereupon he (the Holy Prophet) said: You should put in your best efforts (in their) service. (Using translation from Muslim 2549a)  

جَاءَ رَجُلٌ إِلَى النَّبِيِّ ﷺ يَسْتَأْذِنُهُ فِي الْجِهَادِ فَقَالَ «أَحَيٌّ وَالِدَاكَ؟» قَالَ نَعَمْ قَالَ «فَفِيهِمَا فَجَاهِدْ»