Right on! The context could not be more obvious. Of course Paul is talking of the Lord's evening meal when he refers to "the cup of the Lord" and "the Lord's table."
Luke 22:30 is recorded as being uttered in the night of the institution of the Eucharist. It reads: "that ye may eat and drink at my table (trapezes mou) in my kingdom; and ye shall sit on thrones judging the twelve tribes of Israel." This is the eschatological "table of the Lord" (trapezes kuriou, 1Co 10:21), antecipated in the communion meal discussed in 1 Corinthians 10 and 11.
One thing leads to another: if Kyrios in verse 21 refers to Jesus, to whom does the subsequent "Lord" in verse 22 refer?
1Co 10:21 Ye cannot drink the cup of the Lord, and the cup of devils: ye cannot be partakers of the Lord's table, and of the table of devils.
1Co 10:22 Do we provoke the Lord to jealousy? are we stronger than he?
This last verse is an unambiguous allusion to Deuteronomy 32:16,21 LXX, where the same verb (provoke to jealousy, parazeloumen) is used and applied to Yahweh:
Deu 32:16 They moved him to jealousy with strange gods; With abominations provoked they him to anger.
Deu 32:21 They have moved me to jealousy with that which is not God; They have provoked me to anger with their vanities.
1 Corinthians 10 is pretty much linked to Deuteronomy 32:
Deu 32:17 They sacrificed unto devils, not to God; to gods whom they knew not, to new gods that came newly up, whom your fathers feared not.
1Co 10:20 But I say, that the things which the Gentiles sacrifice, they sacrifice to devils, and not to God: and I would not that ye should have fellowship with devils.
Deu 32:37 And he shall say, Where are their gods, their rock in whom they trusted,
Deu 32:38 Which did eat the fat of their sacrifices, and drank the wine of their drink offerings? let them rise up and help you, and be your protection.
1Co 10:21 Ye cannot drink the cup of the Lord, and the cup of devils: ye cannot be partakers of the Lord's table, and of the table of devils.
Deu 32:18 Of the Rock that begat thee thou art unmindful, and hast forgotten God that formed thee.
1Co 10:4 And did all drink the same spiritual drink: for they drank of that spiritual Rock that followed them: and that Rock was Christ.
Ironically, the "provoking to jealousy" verse in Deu 32 is also quoted in Rom 10. That chapter just happens to be the well-known passage where the NWT interpolates "Jehovah" where "Lord" should be read. "For whosoever shall call upon the name of the Lord shall be saved." (Rom 10:13,19).