summon someone before someone or something
to request or order someone to appear before someone or a group. The president summoned the committee before her. The judge summoned Donna before the court.
summon someone to someone or something
to order or request someone to come to someone or something. Uncle Fred summoned the waitress to him. He summoned her to our table.
summon something up
to call forth particular qualities, such as strength, courage, wisdom, etc. She summoned her courage up and went into the room. Liz summoned up all her courage.