19 The leaders were delighted when Judas contacted them about betraying Jesus, because it gave them the opportunity they had been looking for, and they could later claim that Jesus had been betrayed by one of his own disciples.
20 Matt 26:15 states the amount of money they gave Judas was thirty pieces of silver (see also Matt 27:3–4; Zech 11:12–13).
21 Here καί (kai) has been translated as “so” to indicate the implied result of previous action(s) in the narrative.
22 Grk “he”; the referent (Judas) has been specified in the translation for clarity.

In other versions

And when they heard it, they were glad and promised to give him money. And he sought an opportunity to betray him.

They were delighted to hear this and promised to give him money. So he watched for an opportunity to hand him over.

And when they heard this, they were glad and promised to give him money. So he started looking for a good opportunity to betray him.

They were delighted when they heard why he had come, and they promised to give him money. So he began looking for an opportunity to betray Jesus.

And when they heard this, they were delighted, and promised to give him money. And he began seeking how he could betray him conveniently.

And when they heard it, they were glad, and promised to give him money. And he sought how he might conveniently betray him.

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