The clear teaching of scripture, reason, and experience is that human beings who live their lives outside of Biblical culture are capable of both virtue and the knowledge of God. Those outside of Israel (Christians and Jews, though they are Israel in different ways) and Islam (being a biblically based religion as well despite its divergences) match and sometimes excel Abrahamic folk in our righteousness and communion with God.
According to Refomed Pastor Timothy Keller (who is drawing heavily on Lutheran tradition), the virtue and genius of non-Abrahamics results from "common grace" and "general revelation" (Every Good Endeavour). Common grace is God's good provision for His world, with which he cares for all humankind and all creation. Through common grace God gives the gifts of insight, love, craft, strength, and discovery through which human life is filled with happiness and people have the knowledge and power to create culture and serve each other. Artistic genius, agricultural innovation, medical discoveries, etc. are all gifts of God's care and love for all people. This view implies that Abrahamics can and should find much to celebrate and learn from in all cultures and should not cultivate attitudes of disdain or isolationism.
The doctrine of general revelation states that God also makes Himself known to all people. His image is stamped on our hearts, His laws in our instincts, and nature speaks knowledge of Him (Psalm 19; Romans 1:20). From this point of view knowledge of God, and even of the character and saving work of Christ, can be found in secular culture and non-Abrahamic religions and mythologies. This also includes other religions: Hindus, Buddhists, Sikhs or Confucians have knowledge of virtue and God.
In this regard Jewish and Islamic tradition goes even further: "God has sent prophets to all nations" (Midrash ); "We have sent a messenger to each nation" (Quran 16:36). This view has two fascinating implications: 1) it affirms that the great saints and founders of other religions may have been divinely inspired, and 2) it makes one wonder if other prophets who were more fully divinely inspired from an Abrahamic view may have been rejected or disappeared from history.
According to the Catholic Church
The Catechism of the Catholic Church (CCC) affirms that "Man's faculties make him capable of coming to a knowledge of the existence of a personal God (1.2.35)" and "God, the first principle and last end of things, can be known with certainty from the created world by the light of natural reason (1.3.36)". The "light of natural reason" is therefore capable of functioning well enough apart from Biblical revelation to affirm the existence of God. This perspective meshes well with the early Church's admiration for the best "pagan" philosophers, sages like Aristotle, Plato, Seneca, Marcus Aurelius and Epictetus.
The Protestant view presented here and the view of the Catholic Church are practically speaking very similar. The CCC tends to view the capacity to know God and virtue as inherent to the human being, and the Protestant view as "from outside" and given by grace (a bifurcation which is obviously resonant with similar differences in their greater theologies). On a real life level the Catholic Church has been much more successful in engaging in interfaith dialogue and comparative theology than most Protestant denominations. This seems to me to be related to a tendency in Protestant circles to focus on "natural man's" alienation from God and incapability of virtue without the balancing doctrines of "common grace" and "general revelation" available to them.
Understanding these doctrinal resources from different streams of Abrahamic tradition can be immensely useful to us. They allow us to think on "whatever is true, whatever is noble, whatever is right, whatever is pure, whatever is lovely, whatever is admirable" as Paul advises (Philippians 4:8) while also retaining critical awareness. Just as when assessing our own thoughts and feelings the Biblical revelation is the ultimate authority, so also here when assessing the virtue and wisdom of other minds.
These resources also empower us in our ability to engage with non-Abrahamics with authentic respect and love, and to see God's work in them. Lastly they help us to understand and make sense of both the virtue and genius of non-Abrahamics and the failings and idolatries of our own.