Because he wasn't completely confident he could capture Ling Tian, the Lord of the Universe wanted to draw him into his universe. Worried that Ling Tian had mastered some secret art for suicide—one he couldn't counter, such as self-detonation or burning his soul—the Lord of the Universe could only choose to use Ling Tian's friends and family as leverage to keep him in line. These were the two conditions he had laid before Ling Tian.
Hearing the Lord of the Universe's terms, Ling Tian was overjoyed. They matched the plan they'd initially anticipated and prepared for. He didn't let it show, though; he didn't want to put the Lord of the Universe on guard. Ling Tian had always been skilled at showing weakness to his enemy, and he was even more careful when dealing with the Lord of the Universe. Too much was at stake. The slightest mistake could doom him and his loved ones, and that was the last thing he wanted.
After some "hesitation," Ling Tian finally agreed to the Lord of the Universe's terms. Naturally, he added conditions of his own: his friends and family had to be placed inside his Small World, and the Lord of the Universe had to give him time to "say goodbye" to them.
Ling Tian was undeniably clever. The conditions he'd seized the chance to propose clearly seemed more advantageous to the Lord of the Universe, and at the very least they made it easy to satisfy the two conditions he'd laid out earlier. Ling Tian would enter the Lord of the Universe's universe, and with his loved ones inside his Small World, he wouldn't be able to self-detonate. He was even playing the family card now—the Lord of the Universe knew how much Ling Tian cared about his loved ones,