σκληρότηρ
From LSJ
ἀλλὰ διὰ τῆς ἀγάπης δουλεύετε ἀλλήλοις. ὁ γὰρ πᾶς νόμος ἐν ἑνὶ λόγῳ πεπλήρωται, ἐν τῷ Ἀγαπήσεις τὸν πλησίον σου ὡς σεαυτόν → but be enslaved to each other through love; for the whole Torah is fulfilled in one statement: You will love your neighbor as yourself (Galatians 5:13f.)
English (LSJ)
Eretrian for σκληρότης acc. to Pl.Cra.434c: but final -ς is preserved in Eretrian inscrr., only medial -σ- becoming -ρ-.