"Even before the celebration itself, it is commendable that silence be observed in the church, in the sacristy, in the vesting room, and in adjacent areas, so that all may dispose themselves to carry out the sacred action in a devout and fitting manner."
2. Talking in Church is disrespectful of Jesus in the Blessed Sacrament. We are in the House of God, in the Presence of God Himself in the Tabernacle, not in a coffee shop. All our thoughts should be directed to Him.
3. It teaches disrespect. When children see adults talking, giggling, and laughing in Church, especially before, during, and after the Holy Mass, instead of in prayer or silent meditation it teaches them that its O.K., thus further eroding respect for the Blessed Sacrament in the next generation. And its hypocritical for parents to "shush" their children while they themselves continue to talk.
4. It is the Lord's House, which Jesus taught was "a house of prayer" (Mt 21:13) and thus should be used according to its purpose. It is unholy to turn the Holy House of God into a man-made place of socializing or gossiping. The House of God, where dwells the Real Presence of God, must be treated with ongoing reverence. Talking in Church is a violation of justice against God, for whom we should have reverence.
5. Talking in Church is selfish and a violation of justice against actual neighbors who are trying to pray.
6. Talking in Church is a violation of charity, since as Christians we should be going "out of ourselves" to look after others first. Unnecessary talk in the Church is a total disrespect for one's brothers and sisters in Christ who are trying to pray, and against the faithful who seek to grow in their spiritual lives. Talking in the Church falls short of manifesting love, charity, kindness, and self-control, which are fruits of the Holy Spirit. [Gal. 5:22] If a person crassly and knowingly disregards others trying to pray, or worst of all does so with malice or contempt, it could even be a mortal sin against charity.
