Calvin and the common Catechism: sure knowledge and trust of God’s love in Christ
Better seen from defining justifying faith and its acts/parts.
Reformed definitions vary in wording — nearly the same sense.
Calvin: firm sure knowledge of God’s goodwill to us, on the free promise in Christ, Spirit-revealed and heart-sealed.
Common Catechism: sure persuasion/trust that the Father loves me for Jesus’ sake.
Latin
VII. Sed quomodo fides justificans ab historica differat, ex fidei justificantis definitione, & actuum ac partium ejus expositione melius constare poterit. Porro fides justificans a Reformatis varie describitur, & plures proferuntur ejus definitiones, quae videri possunt plus minusve commodae, sed tamen quoad sensum, eodem fere recidunt. Juxta Calvinum fides justificans est, Divinae erga nos benevolentiae firma certaque cognitio, quae gratuitae in Christo promissionis veritate fundata, per Spiritum Sanctum revelatur mentibus nostris, & cordibus obsignatur: cui consentit descriptio brevis illius Catechismi vulgaris, in quo fides dicitur esse Certa persuasio, vel fiducia quam debet habere quilibet Christianus, quod Deus pater ipsum amat propter filium suum Jesum Christum.