Canto 1 - Boyhood
Bāla-kāṇḍa
Chapter 72: Daśaratha’s Charity Before the Wedding
Text 1.72.3
सदृशो धर्मसम्बन्धः सदृशो रूपसम्पदा।
रामलक्ष्मणयो राजन्सीता चोर्मिलया सह॥
sadṛśo dharma-sambandhaḥ sadṛśo rūpa-sampadā
rāma-lakṣmaṇayo rājan sītā cormilayā saha
sadṛśaḥ = are similar to; dharma-sambandhaḥ = in a religious relationship; sadṛśaḥ = they are also similar; rūpa-sampadā = in terms of the prosperity of beauty; rāma-lakṣmaṇayoḥ = Rāma and Lakṣmaṇa; rājan = O king; sītā ca = Sītā; ūrmilayā saha = and Ūrmilā.
O king, Rāma and Lakṣmaṇa are similar to Sītā and Ūrmilā in a religious relationship. They are also similar in terms of the prosperity of beauty.
The religious relationship here was a matrimonial relationship. Sītā-Rāma and Ūrmilā-Lakṣmaṇa were also similar as their dynasties were similar. Because they are similar in terms of the prosperity of beauty, they could be married.