“You must not act deceptively or lie to one another” (Leviticus 19:11) is one of the many strong, clear statements God made about how to be holy. How to be a person who lives rightly with others – and with God. Although you might be someone who doesn’t care so much about living rightly with God, such instruction still sounds like something we all want as the “best policy” for our relationships. For instance, when we’re getting to know someone who may be our future spouse. Wouldn’t we want our marriage to be grounded in the opposite of deception and lies?

At cinemas this month, new romantic comedy Man Up focuses on a blind date. Nothing terribly unusual about two people – eager for long-term commitment – being set up by friends. But when Jack (Simon Pegg) meets Nancy (Lake Bell) at a London train station, he thinks she is Jessica, his blind date. Nancy doesn’t correct him. She pretends to be Jessica. Laughs flow from the terrible position that desperate Nancy finds herself in – getting to know a man she likes, who thinks he is getting to know someone else.

Simon Pegg and Lake Bell play Jack and Nancy in ‘Man Up’, out today in Australian cinemas

Bell and Pegg are a terrific on-screen team, their rapport helping to sustain an outlandish situation. Thankfully, Man Up doesn’t take itself too seriously or try to be a defining statement about dating in the 21^st Century. But in between the swearing, silly montages and sluggish sequences, a notable undercurrent washes through. Man Up seems to suggest that lying about who you are is okay. Contrary to God and Benjamin Franklin, not being honest isn’t always the best policy according to Man Up. More important is putting yourself out there. Taking chances. Even if that includes faking your identity because, in the end, what does your past matter when the future looks bright?

The relationship built upon lies in Man Up, isn’t as alarming as the abusive marriage at the heart of a new DVD/Blu-ray release. Based on an incredible true story, Big Eyes opens our eyes to Walter Keane (Christoph Waltz). During the 1950s, manipulative fraud Walter shamelessly claimed that he created the celebrated artworks of his wife, Margaret (Amy Adams). Big Eyes looks at their dysfunctional relationship, as fearful Margaret gradually takes a stand against deluded, controlling Walter.

His spectacular lies about being responsible for Margaret’s paintings are much larger and more destructive than anything Man Up serves up. Although Big Eyes too often becomes more straightforward than its subject matter deserves, you should be enthralled by Walter getting away with his sham. Especially as, for some time, Margaret knew what he was doing. Why she became part of his fraud is not just a strong plea for our sympathy. It’s a warning about how important it is to deeply trust that you know, and are known by, who you are married to.

As Man Up and Big Eyes present, pretending to be someone else isn’t a strategy for committed, healthy relationships. But wanting to make ourselves out to be better than we are remains alluring. Admitting the truth can be painful, embarrassing or bitterly disappointing. Ironically, though, we don’t have to pretend to be an improved version of ourselves, if we’re prepared to admit that we aren’t.

In Philippians 3:8-10, the apostle Paul writes he considers “everything to be a loss in view of the surpassing value of knowing Christ Jesus my Lord”. Gaining “the righteousness from God based on faith” in Christ Jesus was so great that it rendered worthless what Paul previously thought important. His status, experience, heritage and achievements became rubbish, due to their impoverished contrast with what knowing – believing, trusting, serving – Jesus caused him to be.

A crucial part of knowing Christ Jesus is not pretending we are the improved version of ourselves. Because we can not be, without honestly admitting how our true selves need what knowing Christ Jesus provides. When we do, we are free to be ourselves improved by God’s righteousness based on faith. Such a renovation means a more trustworthy and open way of relating. Unlike Man Up or Big Eyes, Christians don’t need to lie about who we are. The surpassing value of knowing Christ Jesus transforms us into people who can admit imperfections while pointing to the true self we’re becoming.

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