To be faithful is to be dedicated and devoted to a cause, ideal, or person.
To be faithful, means to be full of faith and to be trustful, not merely trustworthy.
Key verse about Faithful: So if you faithfully obey the commands I am giving you today—to love the Lord your God and to serve him with all your heart and with all your soul— (Deuteronomy 11:13, NIV).
A lifelong student of the Bible, Peter DeHaan, PhD, wrote the 1,000-page website ABibleADay.com to encourage people to explore the Bible. His main blog and many books urge Christians to push past the status quo and reconsider how they practice their faith in every area of their lives.