The following two sections are not superfluous, but they do cover relatively recent territory.
25. In the message which the Church proclaims there are certainly many secondary elements. Their presentation depends greatly on changing circumstances. They themselves also change. But there is the essential content, the living substance, which cannot be modified or ignored without seriously diluting the nature of evangelization itself.
26. It is not superfluous to recall the following points: to evangelize is first of all to bear witness, in a simple and direct way, to God revealed by Jesus Christ, in the Holy Spirit, to bear witness that in His Son God has loved the world – that in His Incarnate Word He has given being to all things and has called men to eternal life. Perhaps this attestation of God will be for many people the unknown God[Cf. Acts 17:22-23] whom they adore without giving Him a name, or whom they seek by a secret call of the heart when they experience the emptiness of all idols. But it is fully evangelizing in manifesting the fact that for (people) the Creator is not an anonymous and remote power; He is the Father: “…that we should be called children of God; and so we are.”[1 Jn 3:1; cf. Rom 8:14-17] And thus we are one another’s brothers and sisters in God.
The notion that people follow God without being explicitly Christian–does that affect evangelization? I wouldn’t think it negates the need to bear witness to Christ and to tell others about him. But it does imply we have a family relationship with any sincere person attempting to find God and to live according to the precepts espoused by the Son, whether they know him or not.
Catholic Sensibility 