If faith's source is from outside the individual and not within, the impetus for faith doesn't come from the individual. God is its source.
Whether or not you affirm Calvinism, that’s a Calvinist assumption - treating faith as something God generates for the individual rather than the person’s volitional response to God’s Word and Spirit. But Scripture is consistent: people are commanded to believe (Acts16:31; John12:36; 1John3:23), and salvation follows faith. It never says God believes on our behalf or implants faith apart from our volitional response. Commands require volitional responses. Scripture’s order stands: choose to believe > salvation.