matha tek

In SGGS or Gurbani, where it is written that “ Sikh should not bow and touch any human being’s feet particularly of a Saint”?

I also have a question, did the Gurus ever encourage others to Matha Tek? Given that they were very very clear about how they should not be worshiped, about how they should not be idolised, that in the big picture, it was Vaheguru that was the object of worship, not themselves, surely they would...