"So Joshua fought the Amalekites as Moses had ordered, and Moses, Aaron and Hur went to the top of the hill. As long as Moses held up his hands, the Israelites were winning, but whenever he lowered his hands, the Amalekites were winning. When Moses' hands grew tired, they took a stone and put it under him and he sat on it. Aaron and Hur held his hands up - one on one side, one on the other - so that his hands remained steady till sunset. So Joshua overcame the Amalekite army with the sword." Exodus 17:10-13 (NIV)
"The key phrase is found in verse 12: “And his hands remained steady...” (vay'hi yadaiv emunah). The word “steady” is actually the Hebrew word for faith, emunah. This important truth can easily escape readers in other languages.
Consequently, they miss the understanding that emunah (faith) fundamentally implies firmness, steadiness, steadfastness, persistence, fidelity or loyalty. In a word, the foundational Hebrew concept of faith is really “faithfulness.” Moses’ hands remained “firm” until the going down of the sun, and through his “faithfulness” Israel triumphed over her foes.
Faithfulness is the victory that overcomes the world (1 John 5:4). To the Hebrew mind, faith is more than belief in something; it is faithfulness to someone. Yes, emunah is related to the word for truth and it does imply trust or belief. But it is more than mental assent to truthful propositions or the confidence that comes from intellectual conviction. Faith is fully Hebraic only when it is fully faithful.
Perhaps we could render it this way: it is “faith/fulness.” Biblical faith is both trust and trustworthiness; both conviction and persistent determination. But it stands or falls on the foundation of faithfulness. “If you do not stand firm in your faith, you will not stand at all” (Isaiah 7:9). To fail to see this is to fall short of the faith of our father, Abraham."