This section of scripture is often misunderstood; let's review it.
Acts 15:10 (KJ) Now therefore why tempt ye Yahweh, to put a yoke upon the neck of the disciples, which neither our fathers nor we were able to bear? Acts 15:19 (KJ) Wherefore my sentence is, that we trouble not them, which from among the Gentiles are turned to Yahweh: Acts 15:20 (KJ) But that we write unto them, that they abstain from pollutions of idols, and [from] fornication, and [from] things strangled, and [from] blood. 21 For Moses of old time hath in every city them that preach him, being read in the synagogues every sabbath day.
The discussion that was in progress before these verses, was whether Gentiles had to be circumcised. At this time the Hebrews had come to beleive, erroneously, that the blood of their circumcision was the blood that sealed the covenant with Yahweh. Paul taught that it is Yahshua's blood that seals the covenant, and so circumcision is no longer necessary; just as the animal sacrifices are no longer necessary. Circumcision was being referred to as a "yoke," not Yahweh's Law (Torah). So, the group agreed not to trouble the Gentiles with circumcision, but to write to them about four major things; and then referred to the fact that the new gentile believers would be hearing the teaching of Moses every Sabbath. So, the Gentile believers were expected to be keeping the Sabbath and learning Torah (Yahweh's teaching, guidance, and direction). Verse 21 is rarely quoted along with 20, because it doesn't fit into the "no Law" doctrine taught at almost all churches.
A correct understanding of these verses is very important. In their previous pagan worship, the gentiles had idols and temple prostitutes. They were being told right up front that this would not be accepable worship before Yahweh. It was felt that they should also be informed about dietary laws where animals must not be strangled, but cut for the blood to be drained from the body. And, one must not drink blood. In summary, no idols, no temple prostitutes, keep the dietary commandments (Lev 11), drink no blood, and learn of the Law each Sabbath.