John 6:63 "It is the Spirit who gives life; the flesh profits nothing. The words that I speak to you are spirit, and they are life."
The words of our Lord Jesus Christ are Spirit for they give life. Only those who has the Spirit of God knows the manifold grace of God (the things freely given to us by God). These will include the grace of salvation, gifts of the Holy Spirit, truth, baptism of the Holy Spirit, Fruit of the Spirit, knowledge of God, understanding His words, will, parables, etc. When anyone dwells on the salvation grace alone that by faith we are saved and not by works, then he has no idea of the manifold grace of God for he has not received the Spirit of God.
1Cor 2:11-12 For what man knows the things of a man except the spirit of the man which is in him? Even so no one knows the things of God except the Spirit of God. Now we have received, not the spirit of the world, but the Spirit who is from God, that we might know the things that have been freely given to us by God.
Rom 8:9-10 But you are not in the flesh but in the Spirit, if indeed the Spirit of God dwells in you. Now if anyone does not have the Spirit of Christ, he is not His. And if Christ is in you, the body is dead because of sin, but the Spirit is life because of righteousness.
When the Spirit of God or the Spirit of Christ dwells in us, our bodies will be dead to sin for we will no longer live according to the flesh but to righteousness. The greatest grace of God is that when we keep His words, the Spirit of God and the Spirit of Christ will dwell in us.
John 14:23 Jesus answered and said to him, "If anyone loves Me, he will keep My word; and My Father will love him, and We will come to him and make Our home with him."
Gal 5:16-21 I say then: Walk in the Spirit, and you shall not fulfill the lust of the flesh. For the flesh lusts against the Spirit, and the Spirit against the flesh; and these are contrary to one another, so that you do not do the things that you wish. But if you are led by the Spirit, you are not under the law. Now the works of the flesh are evident, which are: adultery, fornication, uncleanness, lewdness, idolatry, sorcery, hatred, contentions, jealousies, outbursts of wrath, selfish ambitions, dissensions, heresies, envy, murders, drunkenness, revelries, and the like; of which I tell you beforehand, just as I also told you in time past, that those who practice such things will not inherit the kingdom of God.
Brethren, all those not keeping or reject the words of Jesus are living in the flesh. It is only when we keep His words that we will know truth and the Spirit of God dwells in us.
Rom 8:5-8 For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit, the things of the Spirit. For to be carnally minded is death, but to be spiritually minded is life and peace. Because the carnal mind is enmity against God; for it is not subject to the law of God, nor indeed can be. So then, those who are in the flesh cannot please God.
Ministers of the New Covenant
2 Cor 3:5-6 Not that we are sufficient of ourselves to think of anything as being from ourselves, but our sufficiency is from God, who also made us sufficient as ministers of the new covenant, not of the letter but of the Spirit; for the letter kills, but the Spirit gives life.
Brethren, let's be faithful to our Lord Jesus Christ and ensure that our sheep keep the New Covenant and are His disciples and not Moses' disciples.