Bede : Grace and peace be multiplied to you, etc. In the first Epistle he wrote: Grace and peace be multiplied to you (1 Peter 1). But in this one: Grace and peace be fulfilled to you, because, of course, he wrote the former letter to those beginning, and this one to those more perfect. For peace and grace are multiplied to those advancing well in this life through faith, but will be fulfilled for those arriving in the other life through vision. Hence, well, when saying: Grace and peace be fulfilled to you, he added: In the knowledge of our Lord Jesus Christ. Because this is eternal life (he says), that they know you the only true God, and Jesus Christ whom you have sent (John 17). And again: If the Son sets you free, you will be truly free, and you will know the truth, and the truth will set you free (John 8). — Commentary on the Catholic Epistles John Chrysostom : There is nothing to equal this, which is why we pray and seek after the angel of peace. Everywhere we pray for peace in the churches—in the prayers, in the supplications and in the sermons. And the Guardian of the church gives it to us not once or twice but many times over: "Peace be unto you." Why? Because peace is the mother of all good things and the foundation of our joy. For this reason Christ taught his disciples that when they entered people's houses they were to say: "Peace be unto you." Without peace everything else is useless. — CATENA