Honoring father brings him to sin

 Sefer Chasidim (338) When it is time to do G-d's work nullify your Torah (Tehilim 19) Normally  the son will do the work, even though the father is an ignoramas and let the father be free to do as he pleases. But if the son knows that when the father is sitting idle he is engaged in bad deeds, such as going  after prostitutes, or getting  involved in quarrels and gossip about others or other sins, the commandment is for the son to let his father work so that he does not sin at that time. However if the father tells his son “Go study Torah and I will keep busy by chopping wood or I will take over your job” then the son should study Torah.