Usually, the presence of Saturn in a house has a restrictive effect on the matters that the house rules. You should always keep in mind though that there is a huge difference between a well aspected Saturn and an adversely aspected one. Also, when natal Saturn is located in the signs of Capricorn, Aquarius, Libra or Scorpio he tends to abolish a lot of his negative traits, and can even become benefic if there is no harsh aspect to the other planets present in the chart. Saturn is a slow moving planet and gives delays to issues of the house where it is located. The person who was born with Saturn in the 3rd house usually starts talking and communicating later than other kids, might have a rather slow.
This planet in 3rd house will depend a lot on the aspects it receives: it generally brings seriousness, lucidity, reflection on an intellectual level, but also a certain stiffness sometimes, or a lack of tolerance. If it promotes concentration and judgement, it can also accentuate doubt, distrust or excessive caution. At the level of relations with the entourage it brings stability (with good aspects) or on the contrary dissatisfaction and frustration, as well as complications in all that relates to contacts with the administration, etc… (with negative aspects).
With good aspects of Pluto it improves depth of mind and reflection, with those of neptune a good balance between logic and intuition, with those of Uranus the ability to organize the desired changes, with those of Jupiter l ability to manage, with those of Mars it reinforces tenacity and perseverance, with those of Venus it is a sign of sincerity and loyalty, with those of Mercury it amplifies the logical, methodical and rational side, with those of the Moon there is more seriousness and honesty, with those of the Sun the ability to plan and manage in the long term.
With negative aspects of Pluto too much stiffness and intolerance, with those of Neptune a gap between ideal and realism, with those of Uranus a lack of adaptation, with those of Jupiter a gap between ambition and reality, therefore difficulty of management, with those of Mars a tendency to impose too much, with those of Venus dissatisfaction, with those of Mercury an overly rigid or finicky spirit, with those of the Moon a lack of adaptation in relationships, with those of the Sun, either a lack of tenacity (sun in mutable sign) or an excessive tendency to obstinacy (sun in fixed sign).
As always, we must synthesize the aspects to Saturn taking into account the sign of Saturn and the 3rd house which is the backdrop to the way this domain is experienced.
Each planets have a different effect on you, depending on which house and sign they reside in. In order to find out where they are located in your natal chart, you can use our free birth chart generator. Also, examine the aspects that they form with other planets in your chart. You will understand a lot more about the detailed role that they have in your horoscope.