Scripture proof: the ban on mixed marriages (1 Kings 11:2) — fulfilled in Solomon, not in others
A similar case is God's command forbidding the Israelites to marry their sons or daughters to the daughters or sons of peoples outside God's covenant. God gives as the reason for this command that those foreign nations would otherwise lead the Israelites' hearts astray and turn them toward their gods: 'You shall not go in to them, nor they to you, for they will surely turn your hearts away to follow their gods' (1 Kings 11:2).
This shows that God foreknew with certainty that the Israelites' hearts would be led astray if they entangled themselves in unlawful marriages of this kind. It came true in Solomon, because the condition was met. It did not come true in most other Israelites, because in their case the prior condition did not occur.
Latin
XIII. Simile est quod Deus interdicens Israelitis, ne filios, vel filias suas matrimonio jungerent cum filiabus vel filiis populorum a foedere Dei alienorum, hujus sui praecepti hanc rationem reddit, quod alioqui gentes illae exterae Israelitarum corda seducerent, & inclinarent ad Deos suos. Non ingrediemini ad eas, neque de illis ingredientur ad vestras: certissime enim avertent corda vestra ut sequamini Deos earum, 1 Reg. 11. 2. Unde patet, Deum certo praescivisse Israelitarum corda seductum iri, si illegitimis ejusmodi connubiis sese implicarent. Quod & in Salomone ob conditionem positam impletum est, in plerisque vero aliis Israelitis non item, propterea quod in illis locum non habuit illa conditio antecedens.