I disagree the best age is from when you are small as you have no chance of doing big paap just bhul if you start early you can get a lot done before you get to an age where you can be tempted and won't feel the pull of maya so much by then because of you bandagi (think of Sant ji). Besides veer ji is right we are 'bandey ik dammi' meaning of one breath the current one, no guarantees of the next .