What is the difference between reaching across denominational lines and ecumenism?
Reaching across denominational lines means acknowledging that God has His own people in every group, so fellowship extends across church boundaries. Ecumenism, however, compromises doctrine in order to achieve unity. The two differ: one recognizes believers everywhere without surrendering truth, while the other sacrifices truth for outward union.
Les teaches that he likes to reach across the denominational line, yet he is not an ecumenicalist. He will not compromise in order to have unity. Reaching across lines means recognizing that God knows in every group there are people He wants for His own. Ecumenism, by contrast, seeks unity through compromise. Paul's corrective in 1 Corinthians is that Christ is not divided; Paul was not crucified for anyone, so no teacher should be the object of faith or the basis for division.