26 The phrase ἡ ἀγάπη τοῦ Χριστοῦ (hē agapē tou Christou, “the love of Christ”) could be translated as either objective genitive (“our love for Christ”) or subjective genitive (“Christ’s love for us”). Either is grammatically possible, but with the reference to Christ’s death for all in the following clauses, a subjective genitive (“Christ’s love for us”) is more likely.
27 Grk “one”; the referent (Christ) has been specified in the translation for clarity.

In other versions

For the love of Christ controls us, because we have concluded this: that one has died for all, therefore all have died;

For Christ’s love compels us, because we are convinced that one died for all, and therefore all died.

For the love of Christ compels us, since we have reached this conclusion, that one died for all, and therefore all died.

Either way, Christ’s love controls us. Since we believe that Christ died for all, we also believe that we have all died to our old life.

For the love of Christ controls us, because we have concluded this: that one died for all; as a result all died.

For the love of Christ constraineth us; because we thus judge, that if one died for all, then were all dead:

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