Valmiki Ramayana Ayodhya Kanda Sarga 52 Shloka 55
Original Shlokaन हि शक्या प्रवेष्टुं सा मयाऽयोध्या त्वया विना। राजधानी महेन्द्रस्य यथा दुष्कृतकर्मणा।।2.52.55।।
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त्वया विना without you, मया by me, दुष्कृतकर्मणा by the wicked, महेन्द्रस्य Indra's, राजधानी यथा like the capital, सा अयोध्या that Ayodhya, प्रवेष्टुम् to enter, न हि शक्या not possible.
Just as a sinner cannot enter the capital of Indra (heaven), it is impossible for me to enter Ayodhya without you.