Grant, we beseech thee, O God, that after the example of thy
servant James the Just, brother of our Lord, thy Church may
give itself continually to prayer and to the reconciliation of
all who are at variance and enmity; through the same our
Lord Jesus Christ, who liveth and reigneth with thee and the
Holy Ghost, one God, now and for ever. Amen.
Acts provides clear evidence that James was an important figure in the Christian community of Jerusalem.
When Peter, having miraculously escaped from prison, must flee Jerusalem, he asks that James be informed (12:17). When the Christians of Antioch are concerned over whether Gentile Christians need be circumcised to be saved, they send Paul and Barnabas to confer with the church there, and it is James who utters the definitive judgment (15:13ff). When Paul arrives in Jerusalem to deliver the money he raised for the faithful there, it is James to whom he speaks, and who insists that Paul ritually cleanse himself (21:18)
Read it all here.