... the Apostle Peter declared that the Church was built by the Holy Spirit. For you read that he said: 'God, Who knows the hearts of men, bore witness, giving them the Holy Spirit, even as was given to us; and He made no distinction between us and them, purifying their hearts by faith' (Acts 15:8-9). In which is to be considered, that as Christ is the Cornerstone, Who joined together both peoples into one, so, too, the Holy Spirit made no distinction between the hearts of each people, but united them.