The operative word for "yoke" in Acts 15:10 is ζυγός (zugos) and occurs only six times in the NT, five of which are translated "yoke".
The occurrences of ζυγός describe three different yokes:
1. The Yoke of Jesus in Matt 1128-30
Come to Me, all you who are weary and burdened, and I will give you rest. Take My yoke upon you and learn from Me; for I am gentle and humble in heart, and you will find rest for your souls. For My yoke is easy and My burden is light.”
2. The (figurative) Yoke of (literal) slavery
- 1 Tim 6:1 - All who are under the yoke of slavery should consider their masters worthy of full respect, so that God's name and our teaching may not be slandered.
3. The figurative yoke of slavery to sin and the law
- Gal 5:1 - It is for freedom that Christ has set us free. Stand firm, then, and do not let yourselves be burdened again by a yoke of slavery.
Paul explains what he means by this metaphor in the following verses:
2 Take notice: I, Paul, tell you that if you let yourselves be circumcised, Christ will be of no value to you at all. 3 Again I
testify to every man who gets himself circumcised that he is obligated
to obey the whole law. 4 You who are trying to be justified by the
law have been severed from Christ; you have fallen away from grace.
5 But by faith we eagerly await through the Spirit the hope of righteousness. 6 For in Christ Jesus neither circumcision nor
uncircumcision has any value. All that matters is faith, expressed
through love.
Thus, Paul is discussing the ceremonial law that pointed to Christ and now that the reality of Christ had come (Heb 10:1), the ceremonial law was unnecessary.
Now to Acts 15:10 - Now then, why do you test God by placing on the necks of the disciples a yoke that neither we nor our fathers have been able to bear?
What was this yoke - the entire discussion in Acts 15 is clearly stated in Acts 15:5 -
But some believers from the party of the Pharisees stood up and
declared, “The Gentiles must be circumcised and required to obey the
law of Moses.”
Thus, the "yoke" was the ceremonial law of Moses. it could NOT have been the moral law because Paul so fulsomely praised the moral law as worthy of being kept (see appendix below)
Thus, Peter is saying in Acts 15:10 that the ceremonial law was an unbearable "yoke" by which people tried to earn God's favour and salvation by being good. Paul spends considerable space to teach that keeping the law (whether moral or ceremonial) cannot earn salvation or God's love (Rom 3:20, 4:6, Eph 2:5, 8-10, Gal 2:16). However, salvation means nothing if the grace of God does not transform us to make us good moral citizens of God's kingdom and commandment keepers, 1 John 5:1-3.
APPENDIX - Paul's (and others') praise of the moral law.
Note carefully - the praise of the moral law should NOT be viewed as an end in itself - that would be legalism and an attempt to be saved by keeping the law. Rather, the law cannot be kept at all but must be the natural outworking of the Spirit in the life of the Christian. That is, Christians do NOT keep the moral law (and so a moral) in order to be saved, but keep the law because they are saved. See Eph 2:8-10.
The law is not abolished (Matt 5:17, 18), “anyone who sets aside one of the least commandments and teaches others accordingly will be called least in the kingdom of heaven” (Matt 5:19), “But it is easier for heaven and earth to pass away than for one jot of the Law to become void.” (Luke 16:17), the law is essential because “through the law we become conscious of sin” (Rom 3:21, 7:7, 13), “we uphold the law by faith” (Rom 3:31), “the law is holy, and the commandment is holy, righteous and good” (Rom 7:12), “the law is spiritual” (Rom 7:14), “the law is good” (1 Tim 1:8), keeping the law is to do right (James 2:8). “Do we, then, nullify the law by this faith? Certainly not! Instead, we uphold the law.” (Rom 3:31). “What then? Shall we sin because we are not under law, but under grace? Certainly not!” (Rom 6:15); “we are now slaves of righteousness” (Rom 6:16), or, “slaves to God” (Rom 6:22); “And this is love, that we walk according to His commandments. This is the very commandment you have heard from the beginning, that you must walk in love.” (2 John 6); By this we know that we love the children of God: when we love God and keep His commandments. For this is the love of God, that we keep His commandments. And His commandments are not burdensome (1 John 5:2, 3).