Sounds like they've read you a version of the Miranda Rights: Anything you say can and will offend us. Of course God loves us, God is love. They appear to have made up their minds, so to them what they believe and understand is true. Perhaps they've not had any direct and identifiable experience with God yet, or if they have, they interpret it in their own way. There isn't a lot to say to people who are entirely content with themselves and their lot with no hunger for God. As with the parable of the paralytic, they have to want to be healed. When Jesus asked the paralytic, "Do you want to be healed?", the answer should be obvious, but it isn't. People can be inwardly paralyzed and afflicted, and just be completely adapted to it to the point that it is accepted as normal.
I don't know your family or circumstances, so one can only offer conjecture. Overall though, having one family member convert to a different religion, or to become Christian in a non-religious family, often upsets things quite a bit from what I have observed. Less can definitely be more on many occasions. They have to come to God in their own way. Let them ask if they are interested in something, would be my suggestion. And pray for them everyday.
I can see where they might be coming from, because there are so many religious or non-religion options out there it's hard to discern what all those things are without a great deal of study. Not everyone has the time and inclination to even scratch the surface of religious studies. Perhaps to them, you are just another opinion in a multitude of opinions about something that can't be finally and certainly known in this lifetime.
This is long, but I typed it out for you in case you don't have the book so you can read and digest it for yourself, from St. Theopan the Recluse, (your patron saint?) The Path to Salvation:
How Christian life begins in the Mystery of Baptism
The Mysteries which primarily refer to the beginning of the Christian life are Baptism and repentance. Therefore, the rules concerning the beginning of life in a true Christian way are set forth first under the heading of baptism, and then under repentance.
Baptism is the first Mystery (Sacrament) in Christianity; it makes a Christian man worthy to be vouchsafed the gifts of grace through other Mysteries also. Without it one cannot enter into the Christian world and become a member of the Church. The Pre-eternal Wisdom has made a house for Himself upon earth, and the door leading into this house is the Mystery of Baptism. By this door not only do people enter into the house of God, but at this door also they are clothed in a garment worthy of it; they receive a new name and a sign which is impressed upon the whole being of the one being baptized, by mean of which, later, both heavenly and earthly beings recognize and distinguish them.
A New Creature in Christ Through Holy Baptism
If anyone be in Christ, he is a new creature, teaches the Apostle (II Cor 15.17). This new creature a Christian becomes in Baptism. From the font a man comes out not at all the way he went in. As light is to darkness, as life is to death, so is a baptized man opposed to one who is unbaptized. Conceived in iniquities and born in sins, a man before baptism bear in himself all the poison of sin, with all the weight of its consequences. He is in a condition of God’s disfavor; he is by nature a child of wrath. He is ruined, disordered in himself with relation to his parts and powers, which are directed primarily towards the multiplication of sin. He is in subjection to the influence of satan, who act in him with power by reason of the sin which dwells in him. As a result of all this, after death he is unfailingly the child of hell, where he must be tormented together with its prince and his helpers and servants.
Baptism delivers us from all these evils. It takes away the curse by the power of the Cross of Christ and returns the blessing. Those who are baptized are the children of God, as the Lord Himself has given them the right to be: And if children then heirs; heirs of God and joint-heirs with Christ (Rom 8.17). The Kingdom of Heaven belongs to the baptized person already of satan, who now loses authority over him and the power to act arbitrarily in him. By entrance into the Church—the house of refuge—satan is denied access to the newly baptized one. He finds himself here as in a safe enclosure.
All these are spiritually outward privileges and gifts. But what happens inwardly? The healing of the affliction and injury of sin. The power of grace permeates within and restores here the divine order in all its beauty. It treats the disorder in the structure and relationship of the powers and parts, as well as changing the chief orientation from oneself to God—to pleasing God and increasing one’s good deeds.
Therefore, Baptism is a rebirth or a new birth which puts a man in a renewed condition. The Apostle Paul compare all the baptized with the resurrected Savior, giving us to understand that they also have the same bright nature in their renewal as was possessed by the human nature the Lord Jesus through His resurrection in glory (Roman 6.4). And that the orientation of activity in a baptized person is changed may be seen in the words of the same Apostle, who says in another place they they already should not henceforth live unto themselves, but unto Him who died for them, and rose again (II Cor 5.15). For in that He died, He died unto sin once: but in that He liveth, He liveth unto God (Rom 6.10). We are buried with Him by baptism into death (Rom 6.4); and : Our old man is crucified with Him, that henceforth we should not serve sin (Rom 6.6). And so, the whole activity of a man by the power of Baptism is turned away from oneself and sin, and towards God and righteousness.
Remarkable are the words of the Apostle: That henceforth we should not serve sin, as well as his other words: Sin shall not have dominion over you (Rom 6.14). This gives us to understand that he power which, in our disordered, fallen nature, draws us towards, sin, is not entirely exterminated in Baptism, but is only placed in a condition in which it has no power over us, no dominion over us, and we do not serve it. But it is still in us, it lives and acts, only not as a lord. The primacy from now on belongs to the grace of God and to the soul that consciously gives itself over to it.
Saint Diadochos, explaining the power of Baptism, says that before Baptism sin dwells in the heart and grace acts from outside, but after Baptism, graces settles in the heart and sin attracts us from outside. It is banished from the heart as an enemy from a fortress, and it settles outside, in the parts of the body, from where it acts by means of attacks in a fragmented state. This is why there is a constant tempter, a seducer, but no longer a master: he disturbs and alarms, but does not command. And so, the new life is born in Baptism! (Philokalia, vol. 1).
Here our attention will be directed to how the Christian life begins through Baptism in those who were baptized as children—just how this occurs. For here the beginning of Christian life is put in order in a special way which comes from the relationship of grace to freedom.
You already know that grace descends upon free desire and searching, and that only by the mutual cooperation of these two is there begun the new grace-given life which is in accordance both with grace and with the nature of the free person. The Lord gives grace freely. But He asks that a man seek it and receive it with desire, dedicating himself entirely to God. The fulfillment of this condition in repentance and in the Baptism of adults is clear; but how is it fulfilled in the Baptism of infants?
The next chapter discusses the baptism of infants.
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