It certainly is the part of the Christian man to ascend higher than merely to seek and secure the salvation of his own soul.
Although not all have the office of preaching the word of God, yet a private person who is a member of the church may beget spiritual children to God if he has the occasion and ability to win a poor soul and enlighten him with the faith of the gospel.
But when most people see that God provides an opening for them and a way to instruct the uninformed, they will remain silent, keep their mouths shut, and not say a word… He will be guilty of other people’s sin because he had the means to admonish them and did not.
John Calvin, quoted in Engaging with Calvin (edited by Mark D. Thompson) pp. 36-37.