Al-Baqarah 2:283

Wa-in kuntum AAala safarin walamtajidoo katiban farihanun maqboodatun fa-inamina baAAdukum baAAdan falyu-addiallatheei/tumina amanatahu walyattaqi Allaha rabbahuwala taktumoo ashshahadata waman yaktumhafa-innahu athimun qalbuhu wallahu bimataAAmaloona AAaleem

And if you are on a journey and cannot find a scribe, then a security deposit [should be] taken. And if one of you entrusts another, then let him who is entrusted discharge his trust [faithfully] and let him fear Allāh, his Lord. And do not conceal testimony, for whoever conceals it - his heart is indeed sinful, and Allāh is Knowing of what you do.

If you are on a journey, and find no scribe, then (you may have resort to holding something as) mortgage, taken into possession. However, if one of you trusts the other, then the one who has been trusted should fulfill his trust, and should fear Allah, his Lord. Do not conceal testimony. Whoever conceals it, his heart is surely, sinful. Allah is All-Aware of what you do.