Here is something for those who believe in the “bible alone” without giving credit to the Church that gave it to us in regards to the authority God gave to the Church he founded on the rock of Peter.

1 And some coming down from Judea, taught the brethren: That unless you be circuмcised after the manner of Moses, you cannot be saved.
Ver. 1. Unless you be circuмcised. Many who had been converted from Judaism, held that none, not even converted from paganism, could be saved, unless they were circuмcised, and observed the other ceremonies of the law of Moses. (Witham) --- See Galatians v. 2.

2 And when Paul and Barnabas had no small contest with them, they determined that Paul and Barnabas and certain others of the other side, should go up to the apostles and priests to Jerusalem, about this question.

Ver. 2. To the apostles and priests,[1] where we find again presbyters in Greek, meaning bishops and priests. (Witham) --- Paul...should go to...Jerusalem. We learn from Galatians ii. 2. 4. that St. Paul undertook this journey in consequence of a divine revelation, and was accompanied by Barnabas and Titus, the latter of whom he would not suffer to be circuмcised. Such confidence had he in the rectitude of the opinion he defended. From the example of St. Paul and St. Barnabas, apostles, and men full of the Spirit of God, we learn, that as often as any contest arises about faith, recourse should be had to the supreme visible authority [Saint Peter and his authentic successors] established by Jesus Christ, to have all differences adjusted. This is the order of divine Providence with regard to the Church; without it truth and unity could not be preserved; without it, the Church of God would be more defective and inefficient than any human government. Tell the Church: and if he will not hear the Church, let him be to thee as the heathen and the publican. (Matthew xviii. 17.)

3 They, therefore, being brought on their way by the church, passed through Phœnice, and Samaria, relating the conversion of the Gentiles: and they caused great joy to all the brethren.

4 And when they were come to Jerusalem, they were received by the church, and
by the apostles and ancients, declaring how great things God had done with them.

5 But there arose some of the sect of the Pharisees that believed, saying: They must be circuмcised, and be commanded to observe the law of Moses.

6 And the apostles and ancients assembled to consider of this matter.

7 And when there had been much disputing, Peter, rising up, said to them: Men, brethren, you know that in former days God made choice among us, that the Gentiles by my mouth should hear the word of the gospel, and believe.

Ver. 7. Former days. Literally, in the days of old; that is, at the conversion of Cornelius, many years ago, about the year 35; and it was now 51. (Witham) --- St. Peter at the head of the Council, spoke first; St. James as Bishop of Jerusalem, spoke next, and all, as St. Jerome says, came into the sentence of Peter. (Ep. lxxxix. ad S. Aug. chap. 2.)

8 And God, who knoweth the hearts, gave them testimony, giving the Holy Ghost to them as well as to us.

9 And made no distinction between us and them, purifying their hearts by faith.

10 Now, therefore, why tempt you God, to put a yoke upon the necks of the disciples, which neither our fathers nor we were able to bear?
This is what the people who still don’t realize the Old Covenant has been abolished and fulfilled by the New Covenant.  

Ver. 10. Why tempt you God, by calling in question what he hath sufficiently attested, and approved, and by being incredulous to his promises of giving salvation to the Gentiles, and to all nations. (Witham)

11 But by the grace of the Lord Jesus Christ we believe to be saved, as they also.

Ver. 11. In the historical sense he is speaking of the prosperity of the house of Juda, in the reign of Ezechias, or their return from captivity. But in this respect, it is certain that the prophecy never had its entire accomplishment. The passage in the text is cited from the Septuagint. The Hebrew is, "I will raise up the house of David...that it may possess all the nations," &c. Now it is true that the nations never were subject to the house of David, or known by the name of the people of God; but by their vocation to the gospel, as St. James explains it. (Calmet)

12 And all the multitude held their peace: and gave ear to Barnabas and Paul, relating what great signs and wonders God had wrought among the Gentiles by them.

After Peter had spoken they all held their peace.  They were submitting to his authority.  Where does the Church get her authority to make rules?  God.  Here is the proof.  This is where the statement “Rome has spoken, the matter is finished” comes from.  Peter established the Church in Rome where he was martyred.  The faith spread from there throughout the world.  

13 And after they had held their peace, James answered, saying: Men, brethren, hear me.

14 Simon hath related how God first visited the Gentiles, to take out of them a people to his name.

15 And to this agree the words of the prophets, as it is written:

16 After these things I will return, and will rebuild the tabernacle of David, which is fallen down, and I will rebuild the ruins thereof, and I will set it up:

17 That the rest of men may seek after the Lord, and all nations upon whom my name is invoked, saith the Lord, who doth these things.

18 To the Lord was known his own work from the beginning of the world.

19 Wherefore I judge that they, who from among the Gentiles are converted to God, are not to be disquieted.

Ver. 19. Wherefore I judge, and join my judgment with Peter. St. Chrysostom
thinks that James had a special authority in the Council, as bishop of Jerusalem, and because of the great veneration, which those zealous for the Jєωιѕн law had for him: but his power was certainly inferior to that of St. Peter, who was head of all, as St. Chrysostom teacheth, hom. iii. on the Acts.

20 But that we write to them, that they refrain themselves from the pollutions of idols, and from fornication, and from things strangled, and from blood.

Ver. 20. Things strangled and from blood. In these prohibitions, the Church indulged the particular feelings of the Jєωs, that the bond of union between them and the Gentiles might be more closely united; the latter in these two instances giving way to the prejudices of the former, who in their turn gave up much, by submitting to the abolition of the ceremonial law of Moses. This prohibition was of course only temporary, and to cease with the reasons, which gave rise to it. (Menochius) --- The Jєωs had such a horror of blood, that they considered those who eat it as defiled, and violators of the law of nature. The Lord had in effect from the beginning forbidden the use of blood to Noe [Noah], (Genesis ix. 4.) which he likewise reported in the strongest terms in Leviticus viii. 26.[vii. 26.?] By this we see the great authority of God's Church, and Councils which may make permanent or temporary decrees, such as are fitting for the state of the times or peoples, without any express Scripture at all, and by this authoritative exaction, things become of strict obligation, which previous to it, were in themselves indifferent. (Bristow)

21 For Moses, from ancient times, hath in every city them that preach him in the ѕуηαgσgυєs, where he is read every sabbath.

22 Then it pleased the apostles and ancients, with the whole church, to choose men of their own company, and to send to Antioch, with Paul and Barnabas; Judas, who was surnamed Barsabas, and Silas, chief men among the brethren,

23 Writing by their hands. The apostles and ancients, brethren, to the brethren of the Gentiles, that are at Antioch, and in Syria and Cilicia, greeting.
Ver. 23. The brethren of the Gentiles. Hence we see, that the letter, with the decree of the Council, only regarded those converts, who had been Gentiles; neither are they forbidden to use the Jєωιѕн ceremonies, but a declaration is made, that they have no obligation to follow the said ceremonies and precepts, as it will appear by other places. (Witham)

24 Forasmuch as we have heard, that some, who went out from us, have troubled you with words, subverting your souls, to whom we gave no commands:
This verse addresses the first Protestants before the actual name existed.  They pretend to be the true Church when they are not legitimate successors of the Apostles, submit not Peter and his legitimate successors and do not profess the true faith.  Your friend, stuck in the Old Covenant, not willing to admit authority given to the Church by Christ, is of this group

Ver. 24. Some who went out from us, from Jerusalem, and pretended to speak our
mind, and in our name, but we gave them no such commission. (Witham) --- A proper description of heretics, schismatics, and seditious preachers, who go out from their own superiors, and pretend to teach and preach without any mission, et quomodo prædicabunt nisi mittantur; how can they preach, unless they are sent? (Romans x. 15.)

25 It hath seemed good to us, assembled together, to choose out men, and send them to you, with our dearly beloved Barnabas and Paul,

26 Men who have given their lives for the name of our Lord Jesus Christ.

27 We have sent, therefore, Judas and Silas, who themselves also will, by word of mouth, tell you the same things.

28 For it hath seemed good to the Holy Ghost, and to us, to lay no further burden upon you, than these necessary things:
The Church headed by Peter and his legitimate successors (the Catholic Church) is guided by the Holy Ghost this is another proof from scripture.  

Ver. 28. It hath seemed good to the Holy Ghost, and to us. To us in these matters, wherein by the promises of Christ, we are directed by the Holy Ghost, the spirit of truth, &c. --- Than these necessary things. Necessary at this juncture, and always, if we except that order of abstaining from blood, and things strangled, which was not a perpetual, unchangeable precept, but to last only for a time, as St. Chrysostom observes. (Witham) --- This is the first general council held in the Church, and the model of all succeeding ones. In it the apostles, in a commanding and authoritative manner, laid down the law, which was to be the guide of the faithful, knowing they had a right to impose any regulations in the Church, and that they could not employ this authority but to good purposes, directed as they were by the unerring spirit of truth, which Christ had promised (Matthew xxviii. [28]  20.) should remain with his Church for ever. Hence it would appear that we have no more ground refusing obedience to the voice of the Church at present, than at her first establishment: and that those who will not hear the Church now, speaking in her Councils, would with as little ceremony have opposed the apostles on this occasion, had they lived at the time. By what spirit of seduction has been introduced, and spread, to such an alarming extent, the opinion, that Christianity (the very leading feature of which is to hear and to obey) authorizes unrestricted liberty? Is then authority an unmeaning word? (Haydock)

29 That you abstain from things sacrificed to idols, and from blood, and from things strangled, and from fornication: from which things keeping yourselves, you shall do well. Fare ye well.

Ver. 29. From blood, and from things strangled. The use of these things, though of their own nature indifferent, were here prohibited, to bring the Jєωs more easily to admit of the society of the Gentiles; and to exercise the latter in obedience. But this prohibition was but temporary, and has long since ceased to oblige; more especially in the western churches. (Challoner) --- See note on ver. 20, above.