Lakṣmaṇa knew Rāma’s heart. Rāma wanted Lakṣmaṇa to construct a place for Rāma so that Rāma could be in privacy with Sītā-devī. He didn’t [explicitly] tell Lakṣmaṇa this, but He had it in His mind. [However,] Lakṣmaṇa understood Rāma’s desire.

Kṛtajñena (“who knows how to get things done”) indicates that Lakṣmaṇa knew the how to construct a house just as Daśaratha, who [previously] had no sons for a long time, had a house constructed for Rāma out of extreme affection after determining an auspicious time [for this purpose].

Dharmajñena: Lakṣmaṇa knew the dharma of positioning Himself in a manner pleasing to Rāma by not constructing a place suitable for Himself, though He was the son of a king.

A putra is one who saves [his father] from the hell named Put. [Daśaratha] considered displeasing Rāma to be hell and Lakṣmaṇa wanted to deliver him from that hell by doing that which pleased Rāma. [Rāma considered Lakṣmaṇa to be King Daśaratha’s putra in this sense.]

Lord Rāma considered King Daśaratha to be a dharmātmā (“of dhārmika mind”) because while he was alive, he always did that which pleased Rāma and even later on, he arranged for Lakṣmaṇa to do that which pleased Rāma, just as one makes [permanent] arrangements for water supply.¹

Rāmacandra implied, “My father is not dead. Rather, he has fulfilled all of My desires through You. Indeed, You told Me, ‘I will do everything [You desire].’”