26 For the rest, once this gradation of values and activities is established, it must be admitted that for Christian life to develop itself it must have recourse to external and sensible means; that the Church, being a society of men, cannot exist or develop if it does not enjoy liberty of action, and that its members have the right to find in civil society the possibility of living according to the dictates of their consciences. Consequently, it is quite natural that when the most elementary religious and civil liberties are attacked, Catholic citizens do not resign themselves passively to renouncing those liberties. Notwithstanding, the revindication of these rights and liberties can be, according to the circumstances, more or less opportune, more or less energetic.
Source: Nos Es Muy Conocida (Vatican.va)