‘ And his father in law, the damsel's father, retained him, and he abode with him three days. So they did eat and drink, and lodged there '
The welcome was a clear sign of friendship and willingness to maintain the contract. He prevailed on him to stay some time with him.
“And he abode with him three days.” Three days (a complete period, for three is the number of completeness) was probably the length of time required for such a welcome if it was to indicate genuine acceptance, and for the Levite to also indicate friendship. Things like this were never done in a hurry. (‘Three days' could mean he stayed the night, accepted one day's hospitality as a gesture of friendship and was ready to go on the third day).
“So they did eat and drink, and lodged there.” That is the Levite and his servant. They were very hospitably entertained, and had everything provided for them for their convenience.