'Fast' in the Bible

Jesus therefore said to those of the Jews who had now believed in Him, "As for you, if you hold fast to my teaching, then you are truly my disciples;

So she ran, as fast as she could, to find Simon Peter and the other disciple--the one who was dear to Jesus--and to tell them, "They have taken the Master out of the tomb, and we do not know where they have put Him."

If you remit the sins of any persons, they remain remitted to them. If you bind fast the sins of any, they remain bound."