הלכה על סנהדרין 44:7

From the laws of the commandment is, for example, that which they, may their memory be blessed, said (Sanhedrin 22b) that the prohibition of growing locks with the common priests is only at the time of entering the Temple. But anytime that the common priest does not enter the Temple, he is not [transgressing] the prohibition of growing locks at all. But because the high priest is constantly in the Temple, he is always forbidden to grow locks - as if you were to say, that if by way of duress he stays outside of the Temple a few days, he is nonetheless obligated to not grow locks. And how [long] is the growing of locks? Thirty days, like the nazirite - as undifferentiated naziriteship is no less thirty days. And the rest of its details are elucidated.