You Tube Theology

πίστις means “faith, belief; trust; teaching.”

“When Jesus saw their πίστις, he said to the paralyzed man, ‘Son, your sins are forgiven’ (Mark 2:5).”

“Take heart, daughter,” he said, “your πίστις has healed you" (Matt 9:22).
“By rejecting their πίστις and good conscience, some have shipwrecked the πίστις” (1 Tim 1:19).

Mounce's Expository Dictionary:

Noun: πίστις (pistis), GK G4411 (S G4102), 243x. πίστις means “belief, trust, confidence,” though it can also mean “faithfulness.” (1) Faith can refer to the act of believing, such as having faith in God (Mk. 11:22; 1 Thess. 1:8; 1 Pet. 1:21; Heb. 6:1) and faith in Jesus (Acts 3:16; 20:21; 24:24; Gal. 3:26; Eph. 1:15; Col. 1:4; 1 Tim. 3:13). A major theme in Romans and Galatians is that believers are justified by faith and not by works (Rom. 3:28, 30; 4:5, 11, 12, 13, 16; 5:1, 2; 9:30–32; 10:6; Gal. 2:16; 3:8, 9, 11, 12, 14, 22, 24; 5:5). Paul shows the proper relationship between faith and works. Righteousness is received by faith from first to last (Rom. 1:17). At the same time, true faith produces obedience (Rom. 1:5; 16:26; see also Gal. 5:6; 1 Thess. 1:3; 1 Tim. 1:5; Tit. 1:1; 1 Pet. 1:5). (2) πίστις can also refer to Christian doctrine or collection of beliefs (Jas. 2.17; Phil. 1:27; 1 Tim. 1:13; Tit. 2:2; Jude 3). (3) πίστις can denote a conviction or certainty of belief. Jesus says that if someone tells a mountain to be thrown into the sea and has faith that it will happen, then it will (Mk. 11:23). (4) πίστις can also mean “faithfulness” or “trustworthiness.” Jesus remonstrates with the Pharisees for neglecting justice, mercy and faithfulness (Mt. 23:2).

(The dictionary entry is abridged from “Mounce's Complete Expository Dictionary of Old and New Testament Words” (https://billmounce.com/dictionary).