"this we proclaim concerning the Word of Life"
John has by grammatical deftness shifted the focus from where it would naturally fall in the sentence, on the subject, "we", onto the object of the proclamation. By repetition and position, by the time we get to the subject and verb of statement the full weight of the sentence has already fallen on the object: "that which was from the beginning," "this we proclaim concerning the word of life." John leaves no doubt as to what is important, and in doing so gives us a picture of the responsibility of the Christian: we are to declare Christ.
The Gospel is primarily and fundamentally good news, but while it is good news for us, it is not good news about us. It is good news about God and what He has done for us in sending His Son, Jesus Christ. It our our duty and delight to share this news with others, both by expressing it verbally and by applying it to our lives and effecting change in how we live. The proclamation of the Word of Life is how Christians are born, and should be how we speak, think, and live.