God Almighty is the Only Lord; Omnipresent, Omnipotent and Omniscient. In His eternal condition as LORD, only He has authority to choose His servants.
Of course, the criteria He uses to choose only applies to those who are righteous or, at least, want to live in righteousness.
Then the Lord said to Noah, “Come into the ark, you and all your household, because I have seen that you are righteous before Me in this generation.” Genesis 7.1
Among a generation that was morally and spiritually corrupt, the LORD found a righteous man: Noah.
Those chosen are the righteous or, at least, those who meet the necessary conditions to be justified. How many live in the sin they hate? And how many long to live in integrity and righteousness, but aren’t able to roundup enough strength to turn away from sin?
Sin will not leave you in peace. It is impossible to live in sin and be at peace. The Spirit of God is the Spirit of Peace.
How can you be chosen to serve God, when you are still a slave of sin?
If you find yourself in this condition, yet hunger and thirst for righteousness, the LORD chooses you and gives you faith that will justify you to serve Him. Matthew 5.6
Noah was chosen because he was a righteous man. However, his entire generation was in complete chaos. Spiritual and moral corruption multiplied without any hope of improvement. Noah and his family were the only humans chosen to enter the ark of salvation. The animals of each species were also separated. It is important to note the fact that Noah did not have to choose the animals, hunt them or bring them to the ark. God Himself chose them and sent them, two by two, to the ark. All the others died along with the rest of mankind.
In my opinion, the Holy Spirit continues to “cherish” and choose people who hate sin; people who want to turn away from sin but haven’t been successful; people who are, blindly, searching for salvation in religions.
Mount Sinai separated the righteous from the wicked, those who yearned for justice from those who enjoyed unrighteousness…