Authorized Version
    But when ye sin so against the brethren, and wound their weak conscience, ye sin against Christ.

American Standard Version
    And thus, sinning against the brethren, and wounding their conscience when it is weak, ye sin against Christ.

The Bible in Basic English
    And in this way, doing evil to the brothers, and causing trouble to those whose faith is feeble, you are sinning against Christ.

The Darby Bible
    Now, thus sinning against the brethren, and wounding their weak conscience, ye sin against Christ.

The Webster Bible
    But when ye thus sin against the brethren, and wound their weak conscience, ye sin against Christ.

Young's Literal Translation
    and thus sinning in regard to the brethren, and smiting their weak conscience -- in regard to Christ ye sin;

World English Bible
    Thus, sinning against the brothers, and wounding their conscience when it is weak, you sin against Christ.