He's laying down the law.
they kill the suitors
Telemachus sailed away on swift winds, and the suitors were unable to catch him either when he left Ithaca or when he returned.
Athena
Eurymachus leads them all in their decision to ambush Telemachus.
Antinous suggests to have the suitors killed. Since Telemachus is the only suitor that keeps Antinous from Penelope, if Antinous gets rid of Telemachus and the rest of the suitors, he will be the only one left in the house and Penelope will be forced to marry Antinous.
he's laying down the law.
Odysseus tells Telemachus to hid the weapons so that the suitors can't use them. Telemachus has to say that the weapons are getting "smoke damaged" and he is afraid that the suitors will start hurting themselves with them if they have too much to drink.
Odysseus tells Telemachus to remain calm and not start a fight with the suitors. He advises Telemachus to observe their behavior and wait for the right moment to take action. Odysseus urges his son to trust in him and the plan they have in place to deal with the suitors.
they kill the suitors
Yes. Telemachus fights his mother's suitors in both deed and combat.
the excuse that telemachus gives to the suitors is that he will clean the weapons
Telemachus sailed away on swift winds, and the suitors were unable to catch him either when he left Ithaca or when he returned.
Athena
Eurymachus leads them all in their decision to ambush Telemachus.
Telemachus catches the suitors raiding the storeroom in his household.
He lies to her that Telemachus is in no danger of harm from the suitors.
Odysseus persuades Telemachus by revealing his true identity, proving he is still alive and capable of taking down the suitors. He reassures Telemachus that they have the gods on their side and that together, father and son, they can overcome the suitors' tyranny and restore justice to their home.