13 ἐπί 7 suggests “to all these” as a translation for ἐπὶ πᾶσιν δὲ τούτοις (epi pasin de toutois).
14 The term “virtues” is not in the Greek text, but is included in the translation to specify the antecedent and to make clear the sense of the pronoun “these.”
15 The verb “add,” though not in the Greek text, is implied, picking up the initial imperative “clothe yourselves.”
16 The genitive τῆς τελειότητος (tēs teleiotētos) has been translated as an attributive genitive, “the perfect bond.”

In other versions

And above all these put on love, which binds everything together in perfect harmony.

And over all these virtues put on love, which binds them all together in perfect unity.

Above all, put on love, which is the perfect bond of unity.

Above all, clothe yourselves with love, which binds us all together in perfect harmony.

And to all these things add love, which is the bond of perfection.

And above all these things put on charity, which is the bond of perfectness.

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