Galatians 5:22 English Standard Version (ESV) But the fruit of the Spirit is love, joy, peace, patience, kindness, goodness, faithfulness,
This version translates the Greek word pistis as faithfulness where some other translations simply us the word faith.
Given that we cannot have the fruits of the spirit produced in us until we have placed the faith we have in Christ, then this pisis is different than the one used in Acts 24:24 “faith in Christ”. That bible usage is faith as a conviction of the truth of anything, belief; in the NT of a conviction or belief respecting man’s relationship to God and divine things, generally with the included idea of trust and holy fervour born of faith and joined with it. BLB.ORG
Key to the understanding of what faith is and what faith does is found in these three simple words: “joined with it”. We are in Christ and Christ is in us. Our faith and His faithfulness are joined together in what can be best described as a cooperative effort. He is our Lord and calls us to obey from a standpoint of this loving relationship.
Perhaps rather than faith or even faithfulness, our understanding of this pistis might be obedience of faith.
Hebrews 4:2 English Standard Version (ESV) For good news came to us just as to them, but the message they heard did not benefit them, because they were not united by faith with those who listened.
Faith is a unifying force. To gain any benefit out of the Word of God there has to be this marriage of the mind, soul and body to Christ that is born of love and faith. This is why we are described as the bride of Christ, a bonding, a joining, our faith united together.
Ephesians 4:4-6 English Standard Version
4 There is one body and one Spirit—just as you were called to the one hope that belongs to your call— 5 one Lord, one faith, one baptism, 6 one God and Father of all, who is over all and through all and in all.
Faith joined together.