Manusmriti

siva.sh/manusmriti/2/156

न तेन वृद्धो भवति येनास्य पलितं शिरः । यो वै युवाऽप्यधीयानस्तं देवाः स्थविरं विदुः ॥ १५६ ॥

sanskrit

A man is not therefore (considered) venerable because his head is gray; him who, though young, has learned the Veda, the gods consider to be venerable.

english translation

na tena vRddho bhavati yenAsya palitaM ziraH | yo vai yuvA'pyadhIyAnastaM devAH sthaviraM viduH || 156 ||

hk transliteration by Sanscript