paratithēmi

At its root this word pictures placing one thing in front of another. In the Gospels that is almost always food: a host or a disciple sets a meal before guests, as when Jesus has the loaves and fish set before the crowds. It is the plain language of hospitality, the act of putting something within another person's reach to eat.

The same picture works for the mind as easily as for the table. To "set a parable before" a crowd is to lay it out for them to weigh, and to "set forth" a case is to spread the evidence in the open so hearers can judge it for themselves. What ties food and teaching together is one simple image: something is placed where another person can take it up, whether to eat or to think about.

English keeps the image alive in ordinary phrases like "put it before them" or "lay it out."

When the word turns to committing something of one's own, it draws on a picture from everyday life in the ancient world: handing a valuable over to a trustworthy person for safekeeping, the way someone would leave money or goods on deposit with a friend before a journey. What is deposited stays the owner's; the one who receives it is bound to guard it and return it, or hand it on intact.

That background gives the word its weight in its most famous line, Jesus' dying words, "Father, into your hands I commit my spirit." This is not a resigned surrender but a confident deposit placed in safe hands. Paul uses it the same way for people, committing the Ephesian elders to God, and for teaching: a charge or a body of sound instruction is handed to the next generation to be guarded and passed on unchanged.

The near-synonym παραδίδωμι hands something over outright, even into hostile hands; this word leaves it in trust, to be kept safe. The matching noun παραθήκη names the deposit itself, the thing left in another's keeping.