The greatest of these is love

The blessed apostle described even the higher gifts of the Holy Spirit as things that would vanish.  He points to love as alone without end.  Prophecies will end, languages cease and knowledge will fail, (I Cor 13:8).  As for love, love will never cease.  Actually, all gifts have been given for reasons of temporal use and need and they will surely pass away at the end of the present dispensation.  Love, however, will never be cut off.  It works in us and for us, and not simply in this life.  For when the burden of physical need has been laid aside in the time to come, it will endure, more effectively, more excellently, forever unfailing, clinging to God with more fire and zeal through all the length of incorruption. 

On pursuing a pure heart

Everything we do, our every objective, must be undertaken for the sake of…purity of heart…we must practice the reading of the Scripture, together with all the other virtuous activities…to hold our hearts free of the harm of every dangerous passion and in order to rise step by step to the high point of love.