…Secondly, you may say that you have neither the power nor the means to lead souls to God; though you would willingly do so, you do not know how, as you can neither teach nor preach as did the Apostles. I have often written an answer to this objection though I cannot tell whether I have done so in connection with the Castle. However, as the difficulty probably often crosses your minds on account of the desires our Lord gives you of serving Him, I will now speak of it again. I told you elsewhere how the devil frequently fills our thoughts with great schemes, so that instead of putting our hands to what work we can do to serve our Lord, we may rest satisfied with wishing to perform impossibilities.
You can do much by prayer; and then, do not try to help the whole world, but principally your companions; this work will be all the better because you are the more bound to it. Do you think it is a trifling matter that your humility and mortification, your readiness to serve your sisters, your fervent charity towards them, and your love of God, should be as a fire to enkindle their zeal, and that you should constantly incite them to practise the other virtues? This would be a great work and one most pleasing to our Lord: by thus doing all that is in your power, you would prove to His Majesty your willingness to do still more and He would reward you as if you had won Him many souls. Do you answer: ’This would not be converting my sisters, for they are very good already?’ What business is that of yours? If they were still better, the praise they render God would please Him more and their prayers would be more helpful to their neighbours.
-St. Teresa of Avila. The Interior Castle. Third Edition. London: Thomas Baker, 1921. Christian Classics Ethereal Library.