1 Corinthians 10:1-5
1Co 10:1 Because I do not want you to miss this, brothers — the fact that all our fathers were under that cloud, and all had passed through that sea.
1Co 10:2 And they all had been baptized in that cloud and in that sea for Moses,
1Co 10:3 and they all ate the same spiritual food he provided,
1Co 10:4 and they all drank the same spiritual drink. Because they drank from a spiritual rock that accompanied them, but the rock was Christ.
1Co 10:5 Yet God decided against many of them, because they met with catastrophe in the desert.
Paul had been explaining to the Corinthians that following Christ takes hard work and discipline. Now he warns them about their Jewish ancestors who had decided that just being part of a religious community would be enough. They showed up at all the meetings, were baptized like all the rest, and ate and drank all the appropriate religious food and drink. They had done all the external things to indicate that they had decided for God. But he had not decided for them. Paul is warning against hypocrisy within the church. Merely playing along leads to catastrophe.
LORD, strengthen our resolve to dedicate our lives to the faith we profess – faith in Christ our rock.