To the weak I became weak, that I might win the weak. I have become all things to all people, that by all means I might save some. (1 Cor. 9:22)
When it comes to the issue of contextualization, this particular verse is the most utilized verse for prooftexting. Certainly, there is nothing wrong with trying to reach out to others, or presenting information in an understandable way, or removing stumbling blocks to belief? What does this verse actually teach, and can it be used to promote contextualization, however defined?
The context of this verse outlines what Paul did in reaching out to the Jews who are under the Law, and the Gentiles who are outside it. In other parts of Scripture, the Law with its rituals and ceremonies have been stated to be abrogated with the coming of the New Covenant (cf Col. 2:16-17; Gal. 5:2-6, Heb. 8:13), and therefore participating in these rituals are rendered not necessary at all. However, it is not sin to take part in these rituals per se.
In contrasting being "under the law" and "outside the law", we must realize that the Law here refers especially to the ceremonial aspect of the Jewish religious law. Paul is thus advocating accommodation on something which is not necessary for salvation or the Christian life. Among the Jews, he continues keeping the form of these rituals so that he would not needlessly antagonize them. Among the Gentiles, he lives like a non-Jew who do not observe the Jewish religious laws, since they are not necessary anyway. In both of these scenarios, Paul brings himself to their level by adopting either neutral lifestyle which are both spiritually proper.
In light of this, the type of accommodation and "contextualization" that is biblical is one in which the options are ethically and spiritually neutral. Whatever options made can never violate the biblical rules of conduct — that we should be holy as God is holy (Lev. 11:44-45, 1 Peter 1:16). Paul is manifestly not an antinomian, and it is a mistake to interpret the word "law" as meaning anything other than the religious code of the Old Covenant. Neither is the phrase "by all means" meant to be taken as an absolute, as if prostitution is also a legitimate means (To win prostitutes, you should be one as well?), but the phrase is to be understood in context as referring to all valid means possible.
In conclusion, 1 Cor. 9:22 teaches that we should as much as possible find ways to relate to others. However, such does not give us license to compromise the Christan faith and message, or be a pragmatist who thinks that the ends justify the means. Contextualization that compromises the Christian faith and message cannot therefore utilize 1 Cor. 9:22 as a prooftext, for the context does not lend itself to such an abuse.