In my studies, I try to check the scriptures against one another for harmony, knowing that if all of the scriptures do not harmonize, then I am not understanding the truths within them.
Matt 20:16, For many be called, but few chosen. I take this to mean that God calls many to be his adopted children, but only reveals doctrinal truths to but a few. I believe that Matt 7:13-14 harmonizes with this scripture, in the fact that those who go into the wide gate are the many called and quickened that are believing in false doctrines, and false preachers have lead them to destruction. and the few chosen are those quickened persons who have studied with sincerity to understand the scriptures, and have been revealed the truths of the doctrine of Christ. The life that the narrow path leads to is not eternal life, but an abundant, and joyful life that they are granted to live here as they sojourn in this world. I also believe the scriptures teach that those who will populate heaven will be too many to count, as the stars in heaven, and the sand in the sea shore. Heb 11:12 also harmonizes. There are more, I just can not put my finger on them right now.