You are, I am sure, aware that for you penitence is now no longer limited to disclosing your sins to your confessor, but that you must now bear your sins in mind always, until your heart nearly breaks with their ugly load; and would break, were it not for your firm faith in the mercy of our Lord.
Christ told His friends, that is, His disciples, to beware of the leaven of the Pharisees and scribes, meaning by leaven their false pretence. For hypocrisy is a thing hateful to God, and abominated by man, bringing no reward, and utterly useless for the salvation of the soul, or rather the cause of its perdition. Though sometimes it may escape detection for a little, yet before long it is sure to be laid bare and bring disgrace upon them, like ill-featured women, when they are stripped of that external embellishment which they had produced by artificial means. Hypocrisy, therefore, is a thing foreign to the character of the saints. That it is impossible for those things that are done and said by us to escape the eye of the Deity, He showed by saying: “There is nothing covered that shall not be revealed; neither hid that shall not be known.” For all our words and deeds shall be revealed at the day of judgment.
And the opinion, extremely popular in our times, that 'it's all the same which church you go to; after all, God is one' is in agreement with this tendency. Yes! God is one, but, you know, He also gave us one faith; He created one Church for us, not many different faiths and 'churches.' This is confirmed by the holy Apostle Paul when he says, 'One Lord, one faith, one baptism, one God and Father of all,' and so we Christians should form 'one body and one spirit,' as we are called to 'in one hope of our calling' (Eph. 4:4-6). If there is only one true faith and only one true Church, then as a consequence all other faiths and 'churches' are false, not true. How then can anyone say that all faiths and 'churches' are of equal value and that 'it is all the same which church you go to.' Therefore one can and must speak not of the ecumenical unification of everyone for the creation of some new Church, but only of the restoration of union between all who have fallen away and the one true Church of Christ to which Christ the Savior Himself gave the great and sure promise that 'the gates of hell will not prevail against it' (Matt. 16:18).
If your heart has been softened either by repentance before God or by learning the boundless love of God towards you, do not be proud with those whose hearts are still hard. Remember how long your heart was hard and incorrigible. Seven brothers were ill in one hospital. One recovered from his illness and got up and rushed to serve his other brothers with brotherly love, to speed their recovery. Be like this brother. Consider all men to be your brothers, and sick brothers at that. And if you come to feel that God has given you better health than others, know that it is given through mercy, so in health you may serve your frailer brothers.