Jamieson, Fausset and Brown on Acts 11:21

21. a great number believed--Thus the accession of Cornelius and his party was not the first admission of uncircumcised Gentiles into the Church. (See on Ac 10:1.) Nay, we read of no influence which the accession of Cornelius and his house had on the further progress of the Gospel among the Gentiles; whereas there here open upon us operations upon the Gentiles from quite a different quarter, and attended with ever growing success. The only great object served by the case of Cornelius was the formal recognition of the principles which that case afterwards secured. (See on Ac 15:19-29.)