These verses do not state explicitly that the Gentile is under the law?
Well that is not true UG. God's Word would disagree with you....
Rom 2
28, For he is not a Jew, which is one outwardly; neither is that circumcision, which is outward in the flesh:
29, But he is a Jew, which is one inwardly; and circumcision is that of the heart, in the spirit, and not in the letter; whose praise is not of men, but of God.
Romans 10
10, For with the heart man believeth unto righteousness; and with the mouth confession is made unto salvation.
11, For the scripture saith, Whosoever believeth on him shall not be ashamed.
12, For there is no difference between the Jew and the Greek: for the same Lord over all is rich unto all that call upon him.
Romans 3
19, Now we know that what things soever the law saith, it saith to them who are UNDER THE LAW: that EVERY MOUTH MAY BE STOPPED AND ALL THE WORLD may become guilty before God.
20, Therefore by the deeds of the law there shall NO FLESH be justified in his sight: for by the law is the knowledge of sin.
Romans 2
12, For as many AS MANY HAS HAVE SINNED WITHOUT THE LAW SHALL PERISH WITHOUT THE LAW: and as many as have sinned in the law shall be judged by the law;
God's Word is for everyone and we should believe and follow him who is calling us.
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God's 4th commandment is one of the ten (Exodus 20:8-11) If we knowingly break it when God asks us not to we stand guilty before God of committing sin (James 2:8-12). If we do not seek him in repentance and forgiveness we are in danger of the Judgement (Hebrews 10:26-27)
There is not one scripture in ALL of God's WORD that says God's 4th commandment is now ABOLISHED and we are now commanded to worship God on Sunday in it's place.
Sunday worship is a tradition and teaching of man that has lead many to break the commandments of God. Jesus says that if we follow the traditions of man that break the commandments of God we are not following God (Matthew 15:3-9)
In times of ignorance God winks at but now calls all men every where to REPENT for the KINGDOM of HEAVEN is at HAND (Acts 17:30-31)