Faith, faithfulness, and faithful are all relating to the trust we set on God and that trust we cannot produce by ourselves. The faith is the gracious gift from God and the faithfulness is the fruit of the Holy Spirit.
Let's set a time to study all related teachings in Bible and examine our faith on God. If any deficiencies are identified, I am sure more or less there must be, let's face with them and fix them.
Genesis 32:10
I am unworthy of all the lovingkindness and of all the faithfulness which You have shown to Your servant; for with my staff only I crossed this Jordan, and now I have become two companies.
Genesis 47:29
When the time for Israel to die drew near, he called his son Joseph and said to him, "Please, if I have found favor in your sight, place now your hand under my thigh and deal with me in kindness and faithfulness. Please do not bury me in Egypt,
Numbers 5:27
'When he has made her drink the water, then it shall come about, if she has defiled herself and has been unfaithful to her husband, that the water which brings a curse will go into her and cause bitterness, and her abdomen will swell and her thigh will waste away, and the woman will become a curse among her people.
Deuteronomy 7:9
"Know therefore that the LORD your God, He is God, the faithful God, who keeps His covenant and His lovingkindness to a thousandth generation with
Deuteronomy 32:20
"Then He said, 'I will hide My face from them, I will see what their end shall be; For they are a perverse generation, Sons in whom is no faithfulness.
Deuteronomy 32:51
because you broke faith with Me in the midst of the sons of Israel at the waters of Meribah-kadesh, in the wilderness of Zin, because you did not treat Me as holy in the midst of the sons of Israel.
Joshua 22:16
"Thus says the whole congregation of the LORD, 'What is this unfaithful act which you have committed against the God of Israel, turning away from following the LORD this day, by building yourselves an altar, to rebel against the LORD this day?
Joshua 22:22
"The Mighty One, God, the LORD, the Mighty One, God, the LORD! He knows, and may Israel itself know. If it was in rebellion, or if in an unfaithful act against the LORD do not save us this day!
Joshua 22:31
And Phinehas the son of Eleazar the priest said to the sons of Reuben and to the sons of Gad and to the sons of Manasseh, "Today we know that the LORD is in our midst, because you have not committed this unfaithful act against the LORD; now you have delivered the sons of Israel from the hand of the LORD."
1 Samuel 2:35
'But I will raise up for Myself a faithful priest who will do according to what is in My heart and in My soul; and I will build him an enduring house, and he will walk before My anointed always.
1 Samuel 22:14
Then Ahimelech answered the king and said, "And who among all your servants is as faithful as David, even the king's son-in-law, who is captain over your guard, and is honored in your house?
2 Samuel 20:19
"I am of those who are peaceable and faithful in Israel. You are seeking to destroy a city, even a mother in Israel Why would you swallow up the inheritance of the LORD?"
1 Samuel 26:23
" The LORD will repay each man for his righteousness and his faithfulness; for the LORD delivered you into my hand today, but I refused to stretch out my hand against the LORD'S anointed.
2 Chronicles 12:2
And it came about in King Rehoboam's fifth year, because they had been unfaithful to the LORD, that Shishak king of Egypt came up against Jerusalem
2 Chronicles 26:16
[ Pride Is Uzziah's Undoing ] But when he became strong, his heart was so proud that he acted corruptly, and he was unfaithful to the LORD his God, for he entered the temple of the LORD to burn incense on the altar of incense.
2 Chronicles 26:18
They opposed Uzziah the king and said to him, " It is not for you, Uzziah, to burn incense to the LORD, but for the priests, the sons of Aaron who are consecrated to burn incense. Get out of the sanctuary, for you have been unfaithful and will have no honor from the LORD God."